Table Of Contents
Catalyst 3750 Switch Cisco IOS Commands
clear ip arp inspection statistics
clear ip dhcp snooping database
clear l2protocol-tunnel counters
clear spanning-tree detected-protocols
deny (ARP access-list configuration)
deny (MAC access-list configuration)
ip arp inspection vlan logging
ip dhcp snooping information option
ip dhcp snooping information option allowed-untrusted
ip igmp snooping report-suppression
logging event power-inline-status
mac address-table notification
match (access-map configuration)
match (class-map configuration)
mls qos queue-set output buffers
mls qos queue-set output threshold
mls qos srr-queue input bandwidth
mls qos srr-queue input buffers
mls qos srr-queue input cos-map
mls qos srr-queue input dscp-map
mls qos srr-queue input priority-queue
mls qos srr-queue input threshold
mls qos srr-queue output cos-map
mls qos srr-queue output dscp-map
permit (ARP access-list configuration)
permit (MAC access-list configuration)
renew ip dhcp snooping database
Catalyst 3750 Switch Cisco IOS Commands
aaa accounting dot1x
Use the aaa accounting dot1x global configuration command to enable authentication, authorization, and accounting (AAA) accounting and to create method lists defining specific accounting methods on a per-line or per-interface basis for 802.1x sessions. Use the no form of this command to disable 802.1x accounting.
aaa accounting dot1x {name | default} start-stop {broadcast group {name | radius | tacacs+} [group {name | radius | tacacs+} ... ] | group {name | radius | tacacs+} [group {name | radius | tacacs+} ... ]}
no aaa accounting dot1x {name | default}
Syntax Description
Defaults
AAA accounting is disabled.
Command Modes
Global configuration
Command History
Usage Guidelines
This command requires access to a RADIUS server.
Note
We recommend that you enter the dot1x reauthentication interface configuration command before configuring 802.1x RADIUS accounting on an interface.
Examples
This example shows how to configure 802.1x accounting:
Switch(config)# aaa accounting dot1xSwitch(config)#
Note
Related Commands
Specifies one or more AAA methods for use on interfaces running 802.1x.
Sets the number of seconds between re-authentication attempts.
aaa authentication dot1x
Use the aaa authentication dot1x global configuration command on the switch stack or on a standalone switch to specify the authentication, authorization, and accounting (AAA) method to use on ports complying with IEEE 802.1x. Use the no form of this command to disable authentication.
aaa authentication dot1x {default} method1
no aaa authentication dot1x {default}
Syntax Description
Note
Defaults
No authentication is performed.
Command Modes
Global configuration
Command History
Usage Guidelines
The method argument identifies the method that the authentication algorithm tries in the given sequence to validate the password provided by the client. The only method that is truly 802.1x-compliant is the group radius method, in which the client data is validated against a RADIUS authentication server.
If you specify group radius, you must configure the RADIUS server by entering the radius-server host global configuration command.
Use the show running-config privileged EXEC command to display the configured lists of authentication methods.
Examples
This example shows how to enable AAA and how to create an 802.1x-compliant authentication list. This authentication first tries to contact a RADIUS server. If this action returns an error, the user is not allowed access to the network.
Switch(config)# aaa new-modelSwitch(config)# aaa authentication dot1x default group radiusYou can verify your settings by entering the show running-config privileged EXEC command.
Related Commands
action
Use the action access map configuration command on the switch stack or on a standalone switch to set the action for the VLAN access map entry. Use the no form of this command to set the action to the default value, which is to forward.
action {drop | forward}
no action
Syntax Description
drop
Drop the packet when the specified conditions are matched.
forward
Forward the packet when the specified conditions are matched.
Defaults
The default action is to forward packets.
Command Modes
Access-map configuration
Command History
Usage Guidelines
You enter access-map configuration mode by using the vlan access-map global configuration command.
If the action is drop, you should define the access map, including configuring any access control list (ACL) names in match clauses, before applying the map to a VLAN, or all packets could be dropped.
In access map configuration mode, use the match access map configuration command to define the match conditions for a VLAN map. Use the action command to set the action that occurs when a packet matches the conditions.
The drop and forward parameters are not used in the no form of the command.
Examples
This example shows how to identify and apply a VLAN access map vmap4 to VLANs 5 and 6 that causes the VLAN to forward an IP packet if the packet matches the conditions defined in access list al2:
Switch(config)# vlan access-map vmap4Switch(config-access-map)# match ip address al2Switch(config-access-map)# action forwardSwitch(config-access-map)# exitSwitch(config)# vlan filter vmap4 vlan-list 5-6You can verify your settings by entering the show vlan access-map privileged EXEC command.
Related Commands
archive copy-sw
Use the archive copy-sw privileged EXEC command on the stack master to copy the running image from the flash memory on one stack member to the flash memory on one or more other stack members.
archive copy-sw [/destination-system destination-stack-member-number] [/force-reload] [leave-old-sw] [/no-set-boot] [/overwrite] [/reload] [/safe] source-stack-member-number
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The current software image is not overwritten with the copied image.
Both the software image and HTML files are copied.
The new image is copied to the flash: file system.
The BOOT environment variable is changed to point to the new software image on the flash: file system.
Image names are case sensitive; the image file is provided in tar format.
Note
At least one stack member must be running the image that is to be copied to the switch that has incompatible software.
You can copy the image to more than one specific stack member by repeating the /destination-system destination-stack-member-number option in the command for each stack member to be upgraded. If you do not specify the destination-stack-member-number, the default is to copy the running image file to all stack members.
Using the /safe or /leave-old-sw option can cause the new copied image to fail if there is insufficient flash memory. If leaving the software in place would prevent the new image from fitting in flash memory due to space constraints, an error results.
If you used the /leave-old-sw option and did not overwrite the old image when you copied the new one, you can remove the old image by using the delete privileged EXEC command. For more information, see the "delete" section.
Use the /overwrite option to overwrite the image on the flash device with the copied one.
If you specify the command without the /overwrite option, the algorithm verifies that the new image is not the same as the one on the switch flash device or is not running on any stack members. If the images are the same, the copy does not occur. If the images are different, the old image is deleted, and the new one is copied.
After copying a new image, enter the reload privileged EXEC command to begin using the new image, or specify the /reload or /force-reload option in the archive copy-sw command.
You can enter one or more of these options with the source-stack-member-number option:
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If you enter the source-stack-member-number option before one of the previous options, you can enter only the archive copy-sw source-stack-member-number command.
These are examples of how you can enter the archive copy-sw command:
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Examples
This example shows how to copy the running image from stack member 6 to stack member 8:
Switch# archive copy-sw /destination-system 8 6This example shows how to copy the running image from stack member 6 to all the other stack members:
Switch# archive copy-sw 6This example shows how to copy the running image from stack member 5 to stack member 7. If the image being copied already exists on the second stack member's flash memory, it can be overwritten with the copied one. The system reloads after the image is copied:
Switch# archive copy-sw /destination-system 7 /overwrite /force-reload 5Related Commands
archive download-sw
Use the archive download-sw privileged EXEC command on the switch stack or on a standalone switch to download a new image from a TFTP server to the switch or switch stack and to overwrite or keep the existing image.
archive download-sw {/force-reload | /imageonly | /leave-old-sw | /no-set-boot | /no-version-check | /destination-system stack-member-number | /only-system-type system-type | /overwrite | /reload | /safe} source-url
Syntax Description
Defaults
The current software image is not overwritten with the downloaded image.
Both the software image and HTML files are downloaded.
The new image is downloaded to the flash: file system.
The BOOT environment variable is changed to point to the new software image on the flash: file system.
Image names are case sensitive; the image file is provided in tar format.
Compatibility of the stack protocol version on the image to be downloaded is checked with the version on the switch stack.
Command Modes
Privileged EXEC
Command History
12.1(11)AX
This command was introduced.
12.2(20)SE
The http and https keywords were added.
Usage Guidelines
The /imageonly option removes the HTML files for the existing image if the existing image is being removed or replaced. Only the Cisco IOS image (without the HTML files) is downloaded.
Using the /safe or /leave-old-sw option can cause the new image download to fail if there is insufficient flash memory. If leaving the software in place prevents the new image from fitting in flash memory due to space constraints, an error results.
If you used the /leave-old-sw option and did not overwrite the old image when you downloaded the new one, you can remove the old image by using the delete privileged EXEC command. For more information, see the "delete" section.
Use the /no-version-check option if you want to download an image that has a different stack protocol version than the one existing on the switch stack. You must use this option with the /destination-system option to specify the specific stack member to be upgraded with the image.
Note
You can upgrade more than one specific stack member by repeating the /destination-system option in the command for each stack member to be upgraded.
Use the /overwrite option to overwrite the image on the flash device with the downloaded one.
If you specify the command without the /overwrite option, the download algorithm verifies that the new image is not the same as the one on the switch flash device or is not running on any stack members. If the images are the same, the download does not occur. If the images are different, the old image is deleted, and the new one is downloaded.
After downloading a new image, enter the reload privileged EXEC command to begin using the new image, or specify the /reload or /force-reload option in the archive download-sw command.
Examples
This example shows how to download a new image from a TFTP server at 172.20.129.10 and overwrite the image on the switch:
Switch# archive download-sw /overwrite tftp://172.20.129.10/test-image.tarThis example shows how to download only the software image from a TFTP server at 172.20.129.10 to the switch:
Switch# archive download-sw /imageonly tftp://172.20.129.10/test-image.tarThis example shows how to keep the old software version after a successful download:
Switch# archive download-sw /leave-old-sw tftp://172.20.129.10/test-image.tarThis example shows how to specifically upgrade stack members 6 and 8:
Switch# archive download-sw /imageonly /destination-system 6 /destination-system 8 tftp://172.20.129.10/test-image.tarRelated Commands
archive tar
Use the archive tar privileged EXEC command on the switch stack or on a standalone switch to create a tar file, list files in a tar file, or extract the files from a tar file.
archive tar {/create destination-url flash:/file-url} | {/table source-url} | {/xtract source-url flash:/file-url [dir/file...]}
Syntax Description
Defaults
None
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
Image names are case sensitive.
Examples
This example shows how to create a tar file. The command writes the contents of the new-configs directory on the local flash device to a file named saved.tar on the TFTP server at 172.20.10.30:
Switch# archive tar /create tftp:172.20.10.30/saved.tar flash:/new-configsThis example shows how to display the contents of the c3750-tv0-m.tar file that is in flash memory. The contents of the tar file appear on the screen:
Switch# archive tar /table flash:c3750-tv0-m.tarinfo (219 bytes)c3750-tv0-mz-121/ (directory)c3750-tv0-mz-121/html/ (directory)c3750-tv0-mz-121/html/foo.html (0 bytes)c3750-tv0-mz-121/vegas-tv0-mz-121.bin (610856 bytes)c3750-tv0-mz-121/info (219 bytes)info.ver (219 bytes)This example shows how to display only the c3750-tv0-mz-121/html directory and its contents:
Switch# archive tar /table flash:c3750-tv0-m.tar c3750-tv0-mz-121/htmlc3750-tv0-mz-121/html/ (directory)c3750-tv0-mz-121/html/foo.html (0 bytes)This example shows how to extract the contents of a tar file on the TFTP server at 172.20.10.30. This command extracts just the new-configs directory into the root directory on the local flash file system. The remaining files in the saved.tar file are ignored.
Switch# archive tar /xtract tftp:/172.20.10.30/saved.tar flash:/ new-configsRelated Commands
archive upload-sw
Use the archive upload-sw privileged EXEC command on the switch stack or on a standalone switch to upload an existing switch image to a server.
archive upload-sw [/source-system-num stack member number | /version version_string] destination-url
Syntax Description
Defaults
Uploads the currently running image from the flash: file system.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
You must specify the /source-system-num option to use the /version option. Using these options together uploads the specified image, not the running image, of a specific stack member.
Use the upload feature only if the HTML files associated with the embedded device manager have been installed with the existing image.
The files are uploaded in this sequence: the Cisco IOS image, the HTML files, and info. After these files are uploaded, the software creates the tar file.
Image names are case sensitive.
Examples
This example shows how to upload the currently running on stack member 6 image to a TFTP server at 172.20.140.2:
Switch# archive upload-sw /source-system-num 6 tftp://172.20.140.2/test-image.tarRelated Commands
arp access-list
Use the arp access-list global configuration command on the switch stack or on a standalone switch to define an Address Resolution Protocol (ARP) access control list (ACL) or to add clauses to the end of a previously defined list. Use the no form of this command to delete the specified ARP access list.
arp access-list acl-name
no arp access-list acl-name
This command is available only if your switch is running the enhanced multilayer image (EMI).
Syntax Description
Defaults
No ARP access lists are defined.
Command Modes
Global configuration
Command History
Usage Guidelines
After entering the arp access-list command, you enter ARP access-list configuration mode, and these configuration commands are available:
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Use the permit and deny access-list configuration commands to forward and to drop ARP packets based on the specified matching criteria.
When the ARP ACL is defined, you can apply it to a VLAN by using the ip arp inspection filter vlan global configuration command. ARP packets containing only IP-to-MAC address bindings are compared to the ACL. All other types of packets are bridged in the ingress VLAN without validation. If the ACL permits a packet, the switch forwards it. If the ACL denies a packet because of an explicit deny statement, the switch drops the packet. If the ACL denies a packet because of an implicit deny statement, the switch compares the packet to the list of DHCP bindings (unless the ACL is static, which means that packets are not compared to the bindings).
Examples
This example shows how to define an ARP access list and to permit both ARP requests and ARP responses from a host with an IP address of 1.1.1.1 and a MAC address of 0000.0000.abcd:
Switch(config)# arp access-list static-hostsSwitch(config-arp-nacl)# permit ip host 1.1.1.1 mac host 00001.0000.abcdSwitch(config-arp-nacl)# endYou can verify your settings by entering the show arp access-list privileged EXEC command.
Related Commands
auto qos voip
Use the auto qos voip interface configuration command on the switch stack or on a standalone switch to automatically configure quality of service (QoS) for voice over IP (VoIP) within a QoS domain. Use the no form of this command to return to the default setting.
auto qos voip {cisco-phone | cisco-softphone | trust}
no auto qos voip [cisco-phone | cisco-softphone | trust]
Syntax Description
Defaults
Auto-QoS is disabled on the port.
When auto-QoS is enabled, it uses the ingress packet label to categorize traffic, to assign packet labels, and to configure the ingress and egress queues as shown in Table 2-1.
Table 2-1 Traffic Types, Packet Labels, and Queues
TrafficDSCP3
46
24, 26
48
56
34
-
CoS4
5
3
6
7
3
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CoS-to-Ingress Queue Map
2, 3, 4, 5, 6, 7 (queue 2)
0, 1 (queue 1)
CoS-to-Egress Queue Map
5 (queue 1)
3, 6, 7 (queue 2)
4 (queue 3)
2
(queue 3)0, 1 (queue 4)
1 STP = Spanning Tree Protocol
2 BPDU = bridge protocol data unit
3 DSCP = Differentiated Services Code Point
4 CoS = class of service
Table 2-2 shows the generated auto-QoS configuration for the ingress queues.
Table 2-2 Auto-QoS Configuration for the Ingress Queues
SRR1 shared
1
0, 1
81 percent
67 percent
Priority
2
2, 3, 4, 5, 6, 7
19 percent
33 percent
1 SRR = shaped round robin. Ingress queues support shared mode only.
Table 2-3 shows the generated auto-QoS configuration for the egress queues.
Command Modes
Interface configuration
Command History
12.1(14)EA1
This command was introduced.
12.2(20)SE
The cisco-softphone keyword was added, and the generated auto-QoS configuration changed.
Usage Guidelines
Use this command to configure the QoS appropriate for VoIP traffic within the QoS domain. The QoS domain includes the switch, the interior of the network, and edge devices that can classify incoming traffic for QoS.
In releases earlier than Cisco IOS Release 12.2(20)SE, auto-QoS configures the switch only for VoIP with Cisco IP Phones on switch ports.
In Cisco IOS Release 12.2(20)SE or later, auto-QoS configures the switch for VoIP with Cisco IP Phones on switch and routed ports and for VoIP with devices running the Cisco SoftPhone application. These releases support only Cisco IP SoftPhone Version 1.3(3) or later. Connected devices must use Cisco Call Manager Version 4 or later.
To take advantage of the auto-QoS defaults, you should enable auto-QoS before you configure other QoS commands. You can fine-tune the auto-QoS configuration after you enable auto-QoS.
Note
If this is the first port on which you have enabled auto-QoS, the auto-QoS-generated global configuration commands are executed followed by the interface configuration commands. If you enable auto-QoS on another port, only the auto-QoS-generated interface configuration commands for that port are executed.
When you enable the auto-QoS feature on the first port, these automatic actions occur:
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You can enable auto-QoS on static, dynamic-access, and voice VLAN access, and trunk ports. When enabling auto-QoS with a Cisco IP Phone on a routed port, you must assign a static IP address to the IP phone.
Note
After auto-QoS is enabled, do not modify a policy map or aggregate policer that includes AutoQoS in its name. If you need to modify the policy map or aggregate policer, make a copy of it, and change the copied policy map or policer. To use the new policy map instead of the generated one, remove the generated policy map from the interface, and apply the new policy map.
To display the QoS configuration that is automatically generated when auto-QoS is enabled, enable debugging before you enable auto-QoS. Use the debug auto qos privileged EXEC command to enable auto-QoS debugging. For more information, see the debug auto qos command.
To disable auto-QoS on a port, use the no auto qos voip interface configuration command. Only the auto-QoS-generated interface configuration commands for this port are removed. If this is the last port on which auto-QoS is enabled and you enter the no auto qos voip command, auto-QoS is considered disabled even though the auto-QoS-generated global configuration commands remain (to avoid disrupting traffic on other ports affected by the global configuration). You can use the no mls qos global configuration command to disable the auto-QoS-generated global configuration commands. With QoS disabled, there is no concept of trusted or untrusted ports because the packets are not modified (the CoS, DSCP, and IP precedence values in the packet are not changed). Traffic is switched in pass-through mode (packets are switched without any rewrites and classified as best effort without any policing).
Examples
This example shows how to enable auto-QoS and to trust the QoS labels received in incoming packets when the switch or router connected to the port is a trusted device:
Switch(config)# interface gigabitethernet2/0/1Switch(config-if)# auto qos voip trustYou can verify your settings by entering the show auto qos interface interface-id privileged EXEC command.
Related Commands
Enables debugging of the auto-QoS feature.
Defines the default CoS value of a port or assigns the default CoS to all incoming packets on the port.
mls qos map {cos-dscp dscp1 ... dscp8 | dscp-cos dscp-list to cos}
Defines the CoS-to-DSCP map or the DSCP-to-CoS map.
Allocates buffers to a queue-set.
Assigns shaped round robin (SRR) weights to an ingress queue.
Allocates the buffers between the ingress queues.
Maps CoS values to an ingress queue or maps CoS values to a queue and to a threshold ID.
Maps DSCP values to an ingress queue or maps DSCP values to a queue and to a threshold ID.
Configures the ingress priority queue and guarantees bandwidth.
Maps CoS values to an egress queue or maps CoS values to a queue and to a threshold ID.
Maps DSCP values to an egress queue or maps DSCP values to a queue and to a threshold ID.
Configures the port trust state.
Maps a port to a queue-set.
Displays auto-QoS information.
Displays QoS information at the port level.
Assigns the shaped weights and enables bandwidth shaping on the four egress queues mapped to a port.
Assigns the shared weights and enables bandwidth sharing on the four egress queues mapped to a port.
boot auto-copy-sw
Use the boot auto-copy-sw global configuration command from the stack master to enable the automatic upgrade (auto-upgrade) process. It automatically upgrades a switch in version-mismatch (VM) mode by copying the running software image on any stack member or by copying a tar file image in switch stack flash memory. Use the no form of this command to disable the auto-upgrade process.
boot auto-copy-sw
no boot auto-copy-sw
Syntax Description
This command has no arguments or keywords.
Defaults
Enabled.
Command Modes
Global configuration
Command History
Usage Guidelines
A switch in VM mode is a switch that has a different minor version number than the version on the switch stack. A switch in VM mode cannot join the switch stack as a fully functioning member. If the switch stack has an image that can be copied to a switch in VM mode, the auto-upgrade process automatically copies the image from a stack member to the switch in VM mode. The switch then exits VM mode, reboots, and joins the switch stack as a fully functioning member.
The auto-upgrade process affects only switches in VM mode. It does not affect existing stack members.
Related Commands
Displays the settings of the boot environment variables.
Displays version information for the hardware and firmware.
boot boothlpr
Use the boot boothlpr global configuration command on the switch stack or on a standalone switch to load a special Cisco IOS image, which when loaded into memory, can load a second Cisco IOS image into memory and launch it. This variable is used only for internal development and testing. Use the no form of this command to return to the default setting.
boot boothlpr filesystem:/file-url
no boot boothlpr
Syntax Description
filesystem:
Alias for a flash file system. Use flash: for the system board flash device.
/file-url
The path (directory) and name of a bootable helper image.
Defaults
No helper image is loaded.
Command Modes
Global configuration
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
This command changes the setting of the BOOTHLPR environment variable. For more information, see Appendix A, "Catalyst 3750 Switch Boot Loader Commands"
Related Commands
boot config-file
Use the boot config-file global configuration command on a standalone switch to specify the filename that Cisco IOS uses to read and write a nonvolatile copy of the system configuration. Use the no form of this command to return to the default setting.
boot config-file flash:/file-url
no boot config-file
Syntax Description
Defaults
The default configuration file is flash:config.text.
Command Modes
Global configuration
Command History
Usage Guidelines
This command works properly only from a standalone switch.
Filenames and directory names are case sensitive.
This command changes the setting of the CONFIG_FILE environment variable. For more information, see Appendix A, "Catalyst 3750 Switch Boot Loader Commands."
Related Commands
boot enable-break
Use the boot enable-break global configuration command on a standalone switch to enable interrupting the automatic boot process. Use the no form of this command to return to the default setting.
boot enable-break
no boot enable-break
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled. The automatic boot process cannot be interrupted by pressing the Break key on the console.
Command Modes
Global configuration
Command History
Usage Guidelines
This command works properly only from a standalone switch.
When you enter this command, you can interrupt the automatic boot process by pressing the Break key on the console after the flash file system is initialized.
Note
This command changes the setting of the ENABLE_BREAK environment variable. For more information, see Appendix A, "Catalyst 3750 Switch Boot Loader Commands."
Related Commands
boot helper
Use the boot helper global configuration command on the switch stack or on a standalone switch to dynamically load files during boot loader initialization to extend or patch the functionality of the boot loader. Use the no form of this command to return to the default.
boot helper filesystem:/file-url ...
no boot helper
Syntax Description
Defaults
No helper files are loaded.
Command Modes
Global configuration
Command History
Usage Guidelines
This variable is used only for internal development and testing.
Filenames and directory names are case sensitive.
This command changes the setting of the HELPER environment variable. For more information, see Appendix A, "Catalyst 3750 Switch Boot Loader Commands."
Related Commands
boot helper-config-file
Use the boot helper-config-file global configuration command on the switch stack or on a standalone switch to specify the name of the configuration file to be used by the Cisco IOS helper image. If this is not set, the file specified by the CONFIG_FILE environment variable is used by all versions of Cisco IOS that are loaded. Use the no form of this command to return to the default setting.
boot helper-config-file filesystem:/file-url
no boot helper-config file
Syntax Description
filesystem:
Alias for a flash file system. Use flash: for the system board flash device.
/file-url
The path (directory) and helper configuration file to load.
Defaults
No helper configuration file is specified.
Command Modes
Global configuration
Command History
Usage Guidelines
This variable is used only for internal development and testing.
Filenames and directory names are case sensitive.
This command changes the setting of the HELPER_CONFIG_FILE environment variable. For more information, see Appendix A, "Catalyst 3750 Switch Boot Loader Commands."
Related Commands
boot manual
Use the boot manual global configuration command on a standalone switch to enable manually booting the switch during the next boot cycle. Use the no form of this command to return to the default setting.
boot manual
no boot manual
Syntax Description
This command has no arguments or keywords.
Defaults
Manual booting is disabled.
Command Modes
Global configuration
Command History
Usage Guidelines
This command works properly only from a standalone switch.
The next time you reboot the system, the switch is in boot loader mode, which is shown by the switch: prompt. To boot the system, use the boot boot loader command, and specify the name of the bootable image.
This command changes the setting of the MANUAL_BOOT environment variable. For more information, see Appendix A, "Catalyst 3750 Switch Boot Loader Commands."
Related Commands
boot private-config-file
Use the boot private-config-file global configuration command on a standalone switch to specify the filename that Cisco IOS uses to read and write a nonvolatile copy of the private configuration. Use the no form of this command to return to the default setting.
boot private-config-file filename
no boot private-config-file
Syntax Description
Defaults
The default configuration file is private-config.
Command Modes
Global configuration
Command History
Usage Guidelines
This command works properly only from a standalone switch.
Filenames are case sensitive.
Examples
This example shows how to specify the name of the private configuration file to be pconfig:
Switch(config)# boot private-config-file pconfigRelated Commands
boot system
Use the boot system global configuration command on the switch stack or on a standalone switch to specify the Cisco IOS image to load during the next boot cycle. Use the no form of this command to return to the default setting.
boot system {filesystem:/file-url ...| switch {number | all}}
no boot system
no boot system switch {number | all}
Syntax Description
Defaults
The switch attempts to automatically boot the system by using information in the BOOT environment variable. If this variable is not set, the switch attempts to load and execute the first executable image it can by performing a recursive, depth-first search throughout the flash file system. In a depth-first search of a directory, each encountered subdirectory is completely searched before continuing the search in the original directory.
Command Modes
Global configuration
Command History
Usage Guidelines
Filenames and directory names are case sensitive.
If you enter the boot system filesystem:/file-url command on the stack master, the specified software image is loaded only on the stack master during the next boot cycle.
On the stack master, use the boot system switch number command to specify that the software image is loaded on the specified stack member during the next boot cycle. Use the boot system switch all command to specify that the software image is loaded on all the stack members during the next boot cycle.
When you enter the boot system switch number or the boot system switch all command on the stack master, the stack master checks if a software image is already on the stack member (except on the stack master). If the software image does not exist on the stack member (for example, stack member 1), an error message like this appears:
%Command to set boot system switch all xxx on switch=1 failedIf you are using the archive download-sw privileged EXEC command to maintain system images, you never need to use the boot system command. The boot system command is automatically manipulated to load the downloaded image.
This command changes the setting of the BOOT environment variable. For more information, see Appendix A, "Catalyst 3750 Switch Boot Loader Commands."
Related Commands
channel-group
Use the channel-group interface configuration command on the switch stack or on a standalone switch to assign an Ethernet port to an EtherChannel group. Use the no form of this command to remove an Ethernet port from an EtherChannel group.
channel-group channel-group-number mode {active | {auto [non-silent] | desirable [non-silent] | on} | passive}
no channel-group
Syntax Description
Defaults
No channel groups are assigned.
No mode is configured.
Command Modes
Interface configuration
Command History
12.1(11)AX
This command was introduced.
12.1(14)EA1
The active and passive keywords were added.
12.2(25)SE
The channel-group-number range was changed from 1 to 12 to 1 to 48.
Usage Guidelines
For Layer 2 EtherChannels, you do not have to create a port-channel interface first by using the interface port-channel global configuration command before assigning a physical port to a channel group. Instead, you can use the channel-group interface configuration command. It automatically creates the port-channel interface when the channel group gets its first physical port if the logical interface is not already created. If you create the port-channel interface first, the channel-group-number can be the same as the port-channel-number, or you can use a new number. If you use a new number, the channel-group command dynamically creates a new port channel.
You do not have to disable the IP address that is assigned to a physical port that is part of a channel group, but we strongly recommend that you do so.
You create Layer 3 port channels by using the interface port-channel command followed by the no switchport interface configuration command. You should manually configure the port-channel logical interface before putting the interface into the channel group.
After you configure an EtherChannel, configuration changes that you make on the port-channel interface apply to all the physical ports assigned to the port-channel interface. Configuration changes applied to the physical port affect only the port where you apply the configuration. To change the parameters of all ports in an EtherChannel, apply configuration commands to the port-channel interface, for example, spanning-tree commands or commands to configure a Layer 2 EtherChannel as a trunk.
If you do not specify non-silent with the auto or desirable mode, silent is assumed. The silent mode is used when the switch is connected to a device that is not PAgP-capable and seldom, if ever, sends packets. A example of a silent partner is a file server or a packet analyzer that is not generating traffic. In this case, running PAgP on a physical port prevents that port from ever becoming operational. However, it allows PAgP to operate, to attach the port to a channel group, and to use the port for transmission. Both ends of the link cannot be set to silent.
With the on mode, a usable EtherChannel exists only when a port group in the on mode is connected to another port group in the on mode. The on keyword is the only setting that is supported when the EtherChannel members are from different switches in the switch stack (cross-stack EtherChannel).
Caution
A cross-stack EtherChannel supports up to two 10-Gigabit Ethernet interfaces.
Do not configure an EtherChannel in both the PAgP and LACP modes. EtherChannel groups running PAgP and LACP can coexist on the same switch or on different switches in the stack (but not in a cross-stack configuration). Individual EtherChannel groups can run either PAgP or LACP, but they cannot interoperate.
If you set the protocol by using the channel-protocol interface configuration command, the setting is not overridden by the channel-group interface configuration command.
Do not configure a port that is an active or a not-yet-active member of an EtherChannel as an 802.1x port. If you try to enable 802.1x on an EtherChannel port, an error message appears, and 802.1x is not enabled.
Note
Do not configure a secure port as part of an EtherChannel or an EtherChannel port as a secure port.
For a complete list of configuration guidelines, see the "Configuring EtherChannels" chapter in the software configuration guide for this release.
Caution
Examples
This example shows how to configure an EtherChannel on a single switch in the stack. It assigns two static-access ports in VLAN 10 to channel 5 with the PAgP mode desirable:
Switch# configure terminalSwitch(config)# interface range gigabitethernet2/0/1 -2Switch(config-if-range)# switchport mode accessSwitch(config-if-range)# switchport access vlan 10Switch(config-if-range)# channel-group 5 mode desirableSwitch(config-if-range)# endThis example shows how to configure an EtherChannel on a single switch in the stack. It assigns two static-access ports in VLAN 10 to channel 5 with the LACP mode active:
Switch# configure terminalSwitch(config)# interface range gigabitethernet2/0/1 -2Switch(config-if-range)# switchport mode accessSwitch(config-if-range)# switchport access vlan 10Switch(config-if-range)# channel-group 5 mode activeSwitch(config-if-range)# endThis example shows how to configure a cross-stack EtherChannel. It assigns two ports on stack member 2 and one port on stack member 3 as static-access ports in VLAN 10 to channel 5 with the PAgP and LACP modes disabled (on):
Switch# configure terminalSwitch(config)# interface range gigabitethernet2/0/4 -5Switch(config-if-range)# switchport mode accessSwitch(config-if-range)# switchport access vlan 10Switch(config-if-range)# channel-group 5 mode onSwitch(config-if-range)# exitSwitch(config)# interface gigabitethernet3/0/3Switch(config-if)# switchport mode accessSwitch(config-if)# switchport access vlan 10Switch(config-if)# channel-group 5 mode onSwitch(config-if)# exitYou can verify your settings by entering the show running-config privileged EXEC command.
Related Commands
channel-protocol
Use the channel-protocol interface configuration command on the switch stack or on a standalone switch to restrict the protocol used on a port to manage channeling. Use the no form of this command to return to the default setting.
channel-protocol {lacp | pagp}
no channel-protocol
Syntax Description
lacp
Configure an EtherChannel with the Link Aggregation Control Protocol (LACP).
pagp
Configure an EtherChannel with the Port Aggregation Protocol (PAgP).
Defaults
No protocol is assigned to the EtherChannel.
Command Modes
Interface configuration
Command History
Usage Guidelines
Use the channel-protocol command only to restrict a channel to LACP or PAgP. If you set the protocol by using the channel-protocol command, the setting is not overridden by the channel-group interface configuration command.
You must use the channel-group interface configuration command to configure the EtherChannel parameters. The channel-group command also can set the mode for the EtherChannel.
You cannot enable both the PAgP and LACP modes on an EtherChannel group.
PAgP and LACP are not compatible; both ends of a channel must use the same protocol.
Examples
This example shows how to specify LACP as the protocol that manages the EtherChannel:
Switch(config-if)# channel-protocol lacpYou can verify your settings by entering the show etherchannel [channel-group-number] protocol privileged EXEC command.
Related Commands
Assigns an Ethernet port to an EtherChannel group.
show etherchannel protocol
Displays protocol information the EtherChannel.
class
Use the class policy-map configuration command on the switch stack or on a standalone switch to define a traffic classification match criteria (through the police, set, and trust policy-map class configuration commands) for the specified class-map name. Use the no form of this command to delete an existing class map.
class class-map-name
no class class-map-name
Syntax Description
Defaults
No policy map class-maps are defined.
Command Modes
Policy-map configuration
Command History
Usage Guidelines
Before using the class command, you must use the policy-map global configuration command to identify the policy map and to enter policy-map configuration mode. After specifying a policy map, you can configure a policy for new classes or modify a policy for any existing classes in that policy map. You attach the policy map to a port by using the service-policy interface configuration command.
After entering the class command, you enter policy-map class configuration mode, and these configuration commands are available:
•
•
•
•
•
To return to policy-map configuration mode, use the exit command. To return to privileged EXEC mode, use the end command.
The class command performs the same function as the class-map global configuration command. Use the class command when a new classification, which is not shared with any other ports, is needed. Use the class-map command when the map is shared among many ports.
Examples
This example shows how to create a policy map called policy1. When attached to the ingress direction, it matches all the incoming traffic defined in class1, sets the IP Differentiated Services Code Point (DSCP) to 10, and polices the traffic at an average rate of 1 Mbps and bursts at 20 KB. Traffic exceeding the profile is marked down to a DSCP value obtained from the policed-DSCP map and then sent.
Switch(config)# policy-map policy1Switch(config-pmap)# class class1Switch(config-pmap-c)# set dscp 10Switch(config-pmap-c)# police 1000000 20000 exceed-action policed-dscp-transmitSwitch(config-pmap-c)# exitYou can verify your settings by entering the show policy-map privileged EXEC command.
Related Commands
class-map
Use the class-map global configuration command on the switch stack or on a standalone switch to create a class map to be used for matching packets to the class whose name you specify and to enter class-map configuration mode. Use the no form of this command to delete an existing class map and to return to global configuration mode.
class-map [match-all | match-any] class-map-name
no class-map [match-all | match-any] class-map-name
Syntax Description
Defaults
No class maps are defined.
If neither the match-all or match-any keyword is specified, the default is match-all.
Command Modes
Global configuration
Command History
Usage Guidelines
Use this command to specify the name of the class for which you want to create or modify class-map match criteria and to enter class-map configuration mode.
The class-map command and its subcommands are used to define packet classification, marking, and aggregate policing as part of a globally named service policy applied on a per-port basis.
After you are in quality of service (QoS) class-map configuration mode, these configuration commands are available:
•
•
•
•
•
To define packet classification on a physical-port basis, only one match command per class map is supported. In this situation, the match-all and match-any keywords are equivalent.
Only one access control list (ACL) can be configured in a class map. The ACL can have multiple access control entries (ACEs).
Examples
This example shows how to configure the class map called class1 with one match criterion, which is an access list called 103:
Switch(config)# access-list 103 permit any any dscp 10Switch(config)# class-map class1Switch(config-cmap)# match access-group 103Switch(config-cmap)# exitThis example shows how to delete the class map class1:
Switch(config)# no class-map class1You can verify your settings by entering the show class-map privileged EXEC command.
Related Commands
clear ip arp inspection log
Use the clear ip arp inspection log privileged EXEC command on the switch stack or on a standalone switch to clear the dynamic Address Resolution Protocol (ARP) inspection log buffer.
clear ip arp inspection log
This command is available only if your switch is running the enhanced multilayer image (EMI).
Syntax Description
This command has no arguments or keywords.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear the contents of the log buffer:
Switch# clear ip arp inspection logYou can verify that the log was cleared by entering the show ip arp inspection log privileged command.
Related Commands
clear ip arp inspection statistics
Use the clear ip arp inspection statistics privileged EXEC command on the switch stack or on a standalone switch to clear the dynamic Address Resolution Protocol (ARP) inspection statistics.
clear ip arp inspection statistics [vlan vlan-range]
This command is available only if your switch is running the enhanced multilayer image (EMI).
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear the statistics for VLAN 1:
Switch# clear ip arp inspection statistics vlan 1You can verify that the statistics were deleted by entering the show ip arp inspection statistics vlan 1 privileged EXEC command.
Related Commands
show ip arp inspection statistics
Displays statistics for forwarded, dropped, MAC validation failure, and IP validation failure packets for all VLANs or the specified VLAN.
clear ip dhcp snooping database
Use the clear ip dhcp snooping database privileged EXEC command on the switch stack or on a standalone switch to clear the DHCP binding database agent statistics.
clear ip dhcp snooping database statistics
This command is available only if your switch is running the enhanced multilayer image (EMI).
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
When you enter the clear ip dhcp snooping database statistics command, the switch does not update the entries in the binding database and in the binding file before clearing the statistics.
Examples
This example shows how to clear the DHCP snooping binding database agent statistics:
Switch# clear ip dhcp snooping database statisticsYou can verify that the statistics were cleared by entering the show ip dhcp snooping database privileged EXEC command.
Related Commands
Enables DHCP snooping on a VLAN.
Configures the DHCP snooping binding database agent or the binding file.
Displays the status of DHCP snooping database agent.
clear ipc
Use the clear ipc privileged EXEC command on the switch stack or on a standalone switch to clear Interprocess Communications Protocol (IPC) statistics.
clear ipc {queue-statistics | statistics}
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
You can clear all statistics by using the clear ipc statistics command, or you can clear only the queue statistics by using the clear ipc queue-statistics command.
Examples
This example shows how to clear all statistics:
Switch# clear ipc statisticsThis example shows how to clear only the queue statistics:
Switch# clear ipc queue-statisticsYou can verify that the statistics were deleted by entering the show ipc rpc or the show ipc session privileged EXEC command.
Related Commands
show ipc {rpc | session}
Displays the IPC multicast routing statistics.
clear l2protocol-tunnel counters
Use the clear l2protocol-tunnel counters privileged EXEC command on the switch stack or on a standalone switch to clear the protocol counters in protocol tunnel ports.
clear l2protocol-tunnel counters [interface-id]
Syntax Description
interface-id
(Optional) Specify interface (physical interface or port channel) for which protocol counters are to be cleared.
Defaults
This command has no defaults.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Use this command to clear protocol tunnel counters on the switch or on the specified interface.
Examples
This example shows how to clear Layer 2 protocol tunnel counters on an interface:
Switch# clear l2protocol-tunnel counters gigabitethernet0/3Related Commands
clear lacp
Use the clear lacp privileged EXEC command on the switch stack or on a standalone switch to clear Link Aggregation Control Protocol (LACP) channel-group counters.
clear lacp {channel-group-number counters | counters}
Syntax Description
channel-group-number
(Optional) Channel group number. The range is 1 to 48.
counters
Clear traffic counters.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
12.1(14)EA1
This command was introduced.
12.2(25)SE
The channel-group-number range was changed from 1 to 12 to 1 to 48.
Usage Guidelines
You can clear all counters by using the clear lacp counters command, or you can clear only the counters for the specified channel group by using the clear lacp channel-group-number counters command.
Examples
This example shows how to clear all channel-group information:
Switch# clear lacp countersThis example shows how to clear LACP traffic counters for group 4:
Switch# clear lacp 4 countersYou can verify that the information was deleted by entering the show lacp counters or the show lacp 4 counters privileged EXEC command.
Related Commands
clear mac address-table
Use the clear mac address-table privileged EXEC command on the switch stack or on a standalone switch to delete from the MAC address table a specific dynamic address, all dynamic addresses on a particular interface, all dynamic addresses on stack members, or all dynamic addresses on a particular VLAN. This command also clears the MAC address notification global counters.
clear mac address-table {dynamic [address mac-addr | interface interface-id | vlan vlan-id] | notification}
Note
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
12.1(11)AX
This command was introduced.
12.1(19)EA1
The clear mac-address-table command was replaced by the clear mac address-table command.
Examples
This example shows how to remove a specific MAC address from the dynamic address table:
Switch# clear mac address-table dynamic address 0008.0070.0007You can verify that the information was deleted by entering the show mac address-table privileged EXEC command.
Related Commands
clear pagp
Use the clear pagp privileged EXEC command on the switch stack or on a standalone switch to clear Port Aggregation Protocol (PAgP) channel-group information.
clear pagp {channel-group-number counters | counters}
Syntax Description
channel-group-number
(Optional) Channel group number. The range is 1 to 48.
counters
Clear traffic counters.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
12.1(11)AX
This command was introduced.
12.2(25)SE
The channel-group-number range was changed from 1 to 12 to 1 to 48.
Usage Guidelines
You can clear all counters by using the clear pagp counters command, or you can clear only the counters for the specified channel group by using the clear pagp channel-group-number counters command.
Examples
This example shows how to clear all channel-group information:
Switch# clear pagp countersThis example shows how to clear PAgP traffic counters for group 10:
Switch# clear pagp 10 countersYou can verify that information was deleted by entering the show pagp privileged EXEC command.
Related Commands
clear port-security
Use the clear port-security privileged EXEC command on the switch stack or on a standalone switch to delete from the MAC address table all secure addresses or all secure addresses of a specific type (configured, dynamic, or sticky) on the switch or on an interface.
clear port-security {all | configured | dynamic | sticky} [[address mac-addr | interface interface-id] [vlan vlan-id]]
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear all secure addresses from the MAC address table:
Switch# clear port-security allThis example shows how to remove a specific configured secure address from the MAC address table:
Switch# clear port-security configured address 0008.0070.0007This example shows how to remove all the dynamic secure addresses learned on a specific interface:
Switch# clear port-security dynamic interface gigabitethernet1/0/1This example shows how to remove all the dynamic secure addresses from the address table:
Switch# clear port-security dynamicYou can verify that the information was deleted by entering the show port-security privileged EXEC command.
Related Commands
Enables port security on an interface.
switchport port-security mac-address mac-address
Configures secure MAC addresses.
switchport port-security maximum value
Configures a maximum number of secure MAC addresses on a secure interface.
Displays the port security settings defined for an interface or for the switch.
clear spanning-tree counters
Use the clear spanning-tree counters privileged EXEC command on the switch stack or on a standalone switch to clear the spanning-tree counters.
clear spanning-tree counters [interface interface-id]
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
If the interface-id is not specified, spanning-tree counters are cleared for all interfaces.
Examples
This example shows how to clear spanning-tree counters for all interfaces:
Switch# clear spanning-tree countersRelated Commands
clear spanning-tree detected-protocols
Use the clear spanning-tree detected-protocols privileged EXEC command on the switch stack or on a standalone switch to restart the protocol migration process (force the renegotiation with neighboring switches) on all interfaces or on the specified interface.
clear spanning-tree detected-protocols [interface interface-id]
Syntax Description
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
A switch running the rapid per-VLAN spanning-tree plus (rapid-PVST+) protocol or the Multiple Spanning Tree Protocol (MSTP) supports a built-in protocol migration mechanism that enables it to interoperate with legacy 802.1D switches. If a rapid-PVST+ switch or an MSTP switch receives a legacy 802.1D configuration bridge protocol data unit (BPDU) with the protocol version set to 0, it sends only 802.1D BPDUs on that port. A multiple spanning-tree (MST) switch can also detect that a port is at the boundary of a region when it receives a legacy BPDU, an MST BPDU (Version 3) associated with a different region, or a rapid spanning-tree (RST) BPDU (Version 2).
However, the switch does not automatically revert to the rapid-PVST+ or the MSTP mode if it no longer receives 802.1D BPDUs because it cannot learn whether the legacy switch has been removed from the link unless the legacy switch is the designated switch. Use the clear spanning-tree detected-protocols command in this situation.
Examples
This example shows how to restart the protocol migration process on a port:
Switch# clear spanning-tree detected-protocols interface gigabitethernet2/0/1Related Commands
Displays spanning-tree state information.
Overrides the default link-type setting and enables rapid spanning-tree transitions to the forwarding state.
clear vmps statistics
Use the clear vmps statistics privileged EXEC command on the switch stack or on a standalone switch to clear the statistics maintained by the VLAN Query Protocol (VQP) client.
clear vmps statistics
Syntax Description
This command has no arguments or keywords.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear VLAN Membership Policy Server (VMPS) statistics:
Switch# clear vmps statisticsYou can verify that information was deleted by entering the show vmps statistics privileged EXEC command.
Related Commands
Displays the VQP version, reconfirmation interval, retry count, VMPS IP addresses, and the current and primary servers.
clear vtp counters
Use the clear vtp counters privileged EXEC command on the switch stack or on a standalone switch to clear the VLAN Trunking Protocol (VTP) and pruning counters.
clear vtp counters
Syntax Description
This command has no arguments or keywords.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Examples
This example shows how to clear the VTP counters:
Switch# clear vtp countersYou can verify that information was deleted by entering the show vtp counters privileged EXEC command.
Related Commands
Displays general information about the VTP management domain, status, and counters.
cluster commander-address
You do not need to enter this command from the switch stack or from a standalone cluster member switch. The cluster command switch automatically provides its MAC address to cluster member switches when these switches join the cluster. The cluster member switch adds this information and other cluster information to its running configuration file. Use the no form of this global configuration command from the cluster member switch console port to remove the switch from a cluster only during debugging or recovery procedures.
cluster commander-address mac-address [member number name name]
no cluster commander-address
Syntax Description
Defaults
The switch is not a member of any cluster.
Command Modes
Global configuration
Command History
Usage Guidelines
This command is available only on the cluster command switch stack or the cluster command switch.
A cluster member can have only one cluster command switch.
The cluster member switch retains the identity of the cluster command switch during a system reload by using the mac-address parameter.
You can enter the no form on a cluster member switch to remove it from the cluster during debugging or recovery procedures. You would normally use this command from the cluster member switch console port only when the member has lost communication with the cluster command switch. With normal switch configuration, we recommend that you remove cluster member switches only by entering the no cluster member n global configuration command on the cluster command switch.
When a standby cluster command switch becomes active (becomes the cluster command switch), it removes the cluster commander address line from its configuration.
Examples
This is partial sample output from the running configuration of a cluster member.
Switch(config)# show running-configuration<output truncated>cluster commander-address 00e0.9bc0.a500 member 4 name my_cluster<output truncated>This example shows how to remove a member from the cluster by using the cluster member console.
Switch # configure terminalEnter configuration commands, one per line. End with CNTL/Z.Switch(config)# no cluster commander-addressYou can verify your settings by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
cluster discovery hop-count
Use the cluster discovery hop-count global configuration command on the switch stack or on the a cluster command switch on the cluster command switch to set the hop-count limit for extended discovery of candidate switches. Use the no form of this command to return to the default setting.
cluster discovery hop-count number
no cluster discovery hop-count
Syntax Description
number
Number of hops from the cluster edge that the cluster command switch limits the discovery of candidates. The range is 1 to 7.
Defaults
The hop count is set to 3.
Command Modes
Global configuration
Command History
Usage Guidelines
This command is available only on the cluster command switch stack or cluster command switch. This command does not operate on cluster member switches.
If the hop count is set to 1, it disables extended discovery. The cluster command switch discovers only candidates that are one hop from the edge of the cluster. The edge of the cluster is the point between the last discovered cluster member switch and the first discovered candidate switch.
Examples
This example shows how to set hop count limit to 4. This command is executed on the cluster command switch.
Switch(config)# cluster discovery hop-count 4You can verify your setting by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
Displays a list of candidate switches.
cluster enable
Use the cluster enable global configuration command on a command-capable switch or switch stack to enable it as the cluster command switch, assign a cluster name, and to optionally assign a member number to it. Use the no form of the command to remove all members and to make the cluster command switch a candidate switch.
cluster enable name [command-switch-member-number]
no cluster enable
Syntax Description
Defaults
The switch is not a cluster command switch.
No cluster name is defined.
The member number is 0 when the switch is the cluster command switch.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command on any command-capable switch that is not part of any cluster. This command fails if a device is already configured as a member of the cluster.
You must name the cluster when you enable the cluster command switch. If the switch is already configured as the cluster command switch, this command changes the cluster name if it is different from the previous cluster name.
Examples
This example shows how to enable the cluster command switch, name the cluster, and set the cluster command switch member number to 4.
Switch(config)# cluster enable Engineering-IDF4 4You can verify your setting by entering the show cluster privileged EXEC command on the cluster command switch.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
cluster holdtime
Use the cluster holdtime global configuration command on the switch stack or on the a cluster command switch to set the duration in seconds before a switch (either the command or cluster member switch) declares the other switch down after not receiving heartbeat messages. Use the no form of this command to set the duration to the default value.
cluster holdtime holdtime-in-secs
no cluster holdtime
Syntax Description
holdtime-in-secs
Duration in seconds before a switch (either a command or cluster member switch) declares the other switch down. The range is 1 to 300 seconds.
Defaults
The default holdtime is 80 seconds.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command with the cluster timer global configuration command only on the cluster command switch. The cluster command switch propagates the values to all its cluster members so that the setting is consistent among all switches in the cluster.
The holdtime is typically set as a multiple of the interval timer (cluster timer). For example, it takes (holdtime-in-secs divided by the interval-in-secs) number of heartbeat messages to be missed in a row to declare a switch down.
Examples
This example shows how to change the interval timer and the duration on the cluster command switch.
Switch(config)# cluster timer 3Switch(config)# cluster holdtime 30You can verify your settings by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
cluster member
Use the cluster member global configuration command on the cluster command switch to add candidates to a cluster. Use the no form of the command to remove members from the cluster.
cluster member [n] mac-address H.H.H [password enable-password] [vlan vlan-id]
no cluster member n
Syntax Description
Defaults
A newly enabled cluster command switch has no associated cluster members.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command only on the cluster command switch to add a candidate to or remove a member from the cluster. If you enter this command on a switch other than the cluster command switch, the switch rejects the command and displays an error message.
You must enter a member number to remove a switch from the cluster. However, you do not need to enter a member number to add a switch to the cluster. The cluster command switch selects the next available member number and assigns it to the switch that is joining the cluster.
You must enter the enable password of the candidate switch for authentication when it joins the cluster. The password is not saved in the running or startup configuration. After a candidate switch becomes a member of the cluster, its password becomes the same as the cluster command-switch password.
If a switch does not have a configured hostname, the cluster command switch appends a member number to the cluster command-switch hostname and assigns it to the cluster member switch.
If you do not specify a VLAN ID, the cluster command switch automatically chooses a VLAN and adds the candidate to the cluster.
Examples
This example shows how to add a switch as member 2 with MAC address 00E0.1E00.2222 and the password key to a cluster. The cluster command switch adds the candidate to the cluster through VLAN 3.
Switch(config)# cluster member 2 mac-address 00E0.1E00.2222 password key vlan 3This example shows how to add a switch with MAC address 00E0.1E00.3333 to the cluster. This switch does not have a password. The cluster command switch selects the next available member number and assigns it to the switch that is joining the cluster.
Switch(config)# cluster member mac-address 00E0.1E00.3333You can verify your settings by entering the show cluster members privileged EXEC command on the cluster command switch.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
Displays a list of candidate switches.
Displays information about the cluster members.
cluster outside-interface
Use the cluster outside-interface global configuration command on the switch stack or on the a cluster command switch to configure the outside interface for cluster Network Address Translation (NAT) so that a member without an IP address can communicate with devices outside the cluster. Use the no form of this command to return to the default setting.
cluster outside-interface interface-id
no cluster outside-interface
Syntax Description
interface-id
Interface to serve as the outside interface. Valid interfaces include physical interfaces, port-channels, or VLANs. The port-channel range is 1 to 48. The VLAN range is 1 to 4094.
Defaults
The default outside interface is automatically selected by the cluster command switch.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command only on the cluster command switch. If you enter this command on a cluster member switch, an error message appears.
Examples
This example shows how to set the outside interface to VLAN 1:
Switch(config)# cluster outside-interface vlan 1You can verify your setting by entering the show running-config privileged EXEC command.
Related Commands
cluster run
Use the cluster run global configuration command to enable clustering on a switch. Use the no form of this command to disable clustering on a switch.
cluster run
no cluster run
Syntax Description
This command has no arguments or keywords.
Defaults
Clustering is enabled on all switches.
Command Modes
Global configuration
Command History
Usage Guidelines
When you enter the no cluster run command on a cluster command switch or cluster command switch stack, the cluster command switch is disabled. Clustering is disabled, and the switch cannot become a candidate switch.
When you enter the no cluster run command on a cluster member switch, it is removed from the cluster. Clustering is disabled, and the switch cannot become a candidate switch.
When you enter the no cluster run command on a switch that is not part of a cluster, clustering is disabled on this switch. This switch cannot then become a candidate switch.
Examples
This example shows how to disable clustering on the cluster command switch:
Switch(config)# no cluster runYou can verify your setting by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
cluster standby-group
Use the cluster standby-group global configuration command to enable cluster command-switch redundancy by binding the cluster to an existing Hot Standby Router Protocol (HSRP). Entering the routing-redundancy keyword enables the same HSRP group to be used for cluster command-switch redundancy and routing redundancy. Use the no form of this command to return to the default setting.
cluster standby-group HSRP-group-name [routing-redundancy]
no cluster standby-group
Syntax Description
Defaults
The cluster is not bound to any HSRP group.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command only on the cluster command switch. If you enter it on a cluster member switch, an error message appears.
The cluster command switch propagates the cluster-HSRP binding information to all cluster-HSRP capable members. Each cluster member switch stores the binding information in its NVRAM. The HSRP group name must be a valid standby group; otherwise, the command exits with an error.
The same group name should be used on all members of the HSRP standby group that is to be bound to the cluster. The same HSRP group name should also be used on all cluster-HSRP capable members for the HSRP group that is to be bound. (When not binding a cluster to an HSRP group, you can use different names on the cluster commander and the members.)
Examples
This example shows how to bind the HSRP group named my_hsrp to the cluster. This command is executed on the cluster command switch.
Switch(config)# cluster standby-group my_hsrpThis example shows how to use the same HSRP group named my_hsrp for routing redundancy and cluster redundancy.
Switch(config)# cluster standby-group my_hsrp routing-redundancyThis example shows the error message when this command is executed on a cluster command switch and the specified HSRP standby group does not exist:
Switch(config)# cluster standby-group my_hsrp%ERROR: Standby (my_hsrp) group does not existThis example shows the error message when this command is executed on a cluster member switch:
Switch(config)# cluster standby-group my_hsrp routing-redundancy%ERROR: This command runs on a cluster command switchYou can verify your settings by entering the show cluster privileged EXEC command. The output shows whether redundancy is enabled in the cluster.
Related Commands
cluster timer
Use the cluster timer global configuration command on the switch stack or on the a cluster command switch to set the interval in seconds between heartbeat messages. Use the no form of this command to set the interval to the default value.
cluster timer interval-in-secs
no cluster timer
Syntax Description
Defaults
The interval is 8 seconds.
Command Modes
Global configuration
Command History
Usage Guidelines
Enter this command with the cluster holdtime global configuration command only on the cluster command switch. The cluster command switch propagates the values to all its cluster members so that the setting is consistent among all switches in the cluster.
The holdtime is typically set as a multiple of the heartbeat interval timer (cluster timer). For example, it takes (holdtime-in-secs divided by the interval-in-secs) number of heartbeat messages to be missed in a row to declare a switch down.
Examples
This example shows how to change the heartbeat interval timer and the duration on the cluster command switch:
Switch(config)# cluster timer 3Switch(config)# cluster holdtime 30You can verify your settings by entering the show cluster privileged EXEC command.
Related Commands
Displays the cluster status and a summary of the cluster to which the switch belongs.
define interface-range
Use the define interface-range global configuration command on the switch stack or on a standalone switch to create an interface-range macro. Use the no form of this command to delete the defined macro.
define interface-range macro-name interface-range
no define interface-range macro-name interface-range
Syntax Description
macro-name
Name of the interface-range macro; up to 32 characters.
interface-range
Interface range; for valid values for interface ranges, see "Usage Guidelines."
Defaults
This command has no default setting.
Command Modes
Global configuration
Command History
Usage Guidelines
The macro name is a 32-character maximum character string.
A macro can contain up to five ranges.
All interfaces in a range must be the same type; that is, all Fast Ethernet ports, all Gigabit Ethernet ports, all EtherChannel ports, or all VLANs, but you can combine multiple interface types in a macro.
When entering the interface-range, use this format:
•
•
Valid values for type and interface:
•
VLAN interfaces must have been configured with the interface vlan command (the show running-config privileged EXEC command displays the configured VLAN interfaces). VLAN interfaces not displayed by the show running-config command cannot be used in interface-ranges.
•
•
•
For physical interfaces:
•
•
•
When you define a range, you must enter a space before the hyphen (-), for example:
gigabitethernet1/0/1 - 2
You can also enter multiple ranges. When you define multiple ranges, you must enter a space after the first entry before the comma (,). The space after the comma is optional, for example:
fastethernet1/0/3, gigabitethernet1/0/1 - 2
fastethernet1/0/3 -4, gigabitethernet1/0/1 - 2
Examples
This example shows how to create a multiple-interface macro:
Switch(config)# define interface-range macro1 fastethernet1/0/1 - 2, gigabitethernet1/0/1 - 2Related Commands
delete
Use the delete privileged EXEC command on the switch stack or on a standalone switch to delete a file or directory on the flash memory device.
delete [/force] [/recursive] filesystem:/file-url
Syntax Description
Command Modes
Privileged EXEC
Command History
Usage Guidelines
If you use the /force keyword, you are prompted once at the beginning of the deletion process to confirm the deletion.
If you use the /recursive keyword without the /force keyword, you are prompted to confirm the deletion of every file.
The prompting behavior depends on the setting of the file prompt global configuration command. By default, the switch prompts for confirmation on destructive file operations. For more information about this command, see the Cisco IOS Command Reference for Release 12.1.
Examples
This example shows how to remove the directory that contains the old software image after a successful download of a new image:
Switch# delete /force /recursive flash:/old-imageYou can verify that the directory was removed by entering the dir filesystem: privileged EXEC command.
Related Commands
deny (ARP access-list configuration)
Use the deny Address Resolution Protocol (ARP) access-list configuration command on the switch stack or on a standalone switch to deny an ARP packet based on matches against the DHCP bindings. Use the no form of this command to remove the specified access control entry (ACE) from the access list.
deny {[request] ip {any | host sender-ip | sender-ip sender-ip-mask} mac {any | host sender-mac | sender-mac sender-mac-mask} | response ip {any | host sender-ip | sender-ip sender-ip-mask} [{any | host target-ip | target-ip target-ip-mask}] mac {any | host sender-mac | sender-mac sender-mac-mask} [{any | host target-mac | target-mac target-mac-mask}]} [log]
no deny {[request] ip {any | host sender-ip | sender-ip sender-ip-mask} mac {any | host sender-mac | sender-mac sender-mac-mask} | response ip {any | host sender-ip | sender-ip sender-ip-mask} [{any | host target-ip | target-ip target-ip-mask}] mac {any | host sender-mac | sender-mac sender-mac-mask} [{any | host target-mac | target-mac target-mac-mask}]} [log]
This command is available only if your switch is running the enhanced multilayer image (EMI).
Syntax Description
Defaults
There are no default settings. However, at the end of the ARP access list, there is an implicit deny ip any mac any command.
Command Modes
ARP access-list configuration
Command History
Usage Guidelines
You can add deny clauses to drop ARP packets based on matching criteria.
Examples
This example shows how to define an ARP access list and to deny both ARP requests and ARP responses from a host with an IP address of 1.1.1.1 and a MAC address of 0000.0000.abcd:
Switch(config)# arp access-list static-hostsSwitch(config-arp-nacl)# deny ip host 1.1.1.1 mac host 0000.0000.abcdSwitch(config-arp-nacl)# endYou can verify your settings by entering the show arp access-list privileged EXEC command.
Related Commands
deny (MAC access-list configuration)
Use the deny MAC access-list configuration command on the switch stack or on a standalone switch to prevent non-IP traffic from being forwarded if the conditions are matched. Use the no form of this command to remove a deny condition from the named MAC access list.
{deny | permit} {any | host src-MAC-addr | src-MAC-addr mask} {any | host dst-MAC-addr | dst-MAC-addr mask} [type mask | aarp | amber | cos cos | dec-spanning | decnet-iv | diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | lsap lsap mask |mop-console | mop-dump | msdos | mumps | netbios | vines-echo | vines-ip | xns-idp]
no {deny | permit} {any | host src-MAC-addr | src-MAC-addr mask} {any | host dst-MAC-addr | dst-MAC-addr mask} [type mask | aarp | amber | cos cos | dec-spanning | decnet-iv | diagnostic | dsm | etype-6000 | etype-8042 | lat | lavc-sca | lsap lsap mask | mop-console | mop-dump | msdos | mumps | netbios | vines-echo | vines-ip | xns-idp]
Syntax Description
Note
To filter IPX traffic, you use the type mask or lsap lsap mask keywords, depending on the type of IPX encapsulation being used. Filter criteria for IPX encapsulation types as specified in Novell terminology and Cisco IOS terminology are listed in Table 2-4.
Defaults
This command has no defaults. However; the default action for a MAC-named ACL is to deny.
Command Modes
MAC-access list configuration
Command History
Usage Guidelines
You enter MAC-access list configuration mode by using the mac access-list extended global configuration command.
If you use the host keyword, you cannot enter an address mask; if you do not use the host keyword, you must enter an address mask.
When an access control entry (ACE) is added to an access control list, an implied deny-any-any condition exists at the end of the list. That is, if there are no matches, the packets are denied. However, before the first ACE is added, the list permits all packets.
Note
Examples
This example shows how to define the named MAC extended access list to deny NETBIOS traffic from any source to MAC address 00c0.00a0.03fa. Traffic matching this list is denied.
Switch(config-ext-macl)# deny any host 00c0.00a0.03fa netbios.This example shows how to remove the deny condition from the named MAC extended access list:
Switch(config-ext-macl)# no deny any 00c0.00a0.03fa 0000.0000.0000 netbios.This example denies all packets with Ethertype 0x4321:
Switch(config-ext-macl)# deny any any 0x4321 0You can verify your settings by entering the show access-lists privileged EXEC command.
Related Commands
dot1x
Use the dot1x global configuration command on the switch stack or on a standalone switch to globally enable 802.1x. Use the no form of this command to return to the default setting.
dot1x {system-auth-control} | {guest-vlan supplicant}
no dot1x {system-auth-control} | {guest-vlan supplicant}
Syntax Description
system-auth-control
Enable 802.1x globally on the switch.
guest-vlan supplicant
Enable optional guest VLAN behavior globally on the switch.
Defaults
802.1x is disabled, and the optional guest VLAN behavior is disabled.
Command Modes
Global configuration
Command History
12.1(14)EA1
This command was introduced.
12.2(25)SE
The guest-vlan supplicant keywords were added.
Usage Guidelines
You must enable authentication, authorization, and accounting (AAA) and specify the authentication method list before globally enabling 802.1x. A method list describes the sequence and authentication methods to be queried to authenticate a user.
Before globally enabling 802.1x on a switch, remove the EtherChannel configuration from the interfaces on which 802.1x and EtherChannel are configured.
If you are using a device running the Cisco Access Control Server (ACS) application for 802.1x authentication with EAP-Transparent LAN Services (TLS) and with EAP-MD5 and your switch is running Cisco IOS Release 12.1(14)EA1, make sure that the device is running ACS Version 3.2.1 or later.
You can use the guest-vlan supplicant keywords to enable the optional 802.1x guest VLAN behavior globally on the switch. For more information, see the dot1x guest-vlan command.
Examples
This example shows how to globally enable 802.1x on a switch:
Switch(config)# dot1x system-auth-controlThis example shows how to globally enable the optional guest VLAN behavior on a switch:
Switch(config)# dot1x guest-vlan supplicantYou can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
Enables and specifies an active VLAN as an 802.1x guest VLAN.
Enables manual control of the authorization state of the port.
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x default
Use the dot1x default interface configuration command on the switch stack or on a standalone switch to reset the configurable 802.1x parameters to their default values.
dot1x default
Syntax Description
This command has no arguments or keywords.
Defaults
These are the default values:
•
•
•
•
•
•
•
•
•
Command Modes
Interface configuration
Command History
12.1(11)AX
This command was introduced.
12.1(14)EA1
This command was changed to the interface configuration mode.
Examples
This example shows how to reset the configurable 802.1x parameters on a port:
Switch(config-if)# dot1x defaultYou can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x guest-vlan
Use the dot1x guest-vlan interface configuration command on the switch stack or on a standalone switch to specify an active VLAN as an 802.1x guest VLAN. Use the no form of this command to return to the default setting.
dot1x guest-vlan vlan-id
no dot1x guest-vlan
Syntax Description
Defaults
No guest VLAN is configured.
Command Modes
Interface configuration
Command History
12.1(14)EA1
This command was introduced.
12.2(25)SE
This command was modified to change the default guest VLAN behavior.
Usage Guidelines
For each 802.1x port on the switch, you can configure a guest VLAN to provide limited services to clients (a device or workstation connected to the switch), such as downloading the 802.1x client software. These users might be upgrading their systems for 802.1x authentication, and some hosts, such as Windows 98 systems, might not be 802.1x-capable.
When you enable a guest VLAN on an 802.1x port, the switch assigns clients to a guest VLAN when the authentication server does not receive a response to its Extensible Authentication Protocol over LAN (EAPOL) request/identity frame or when EAPOL packets are not sent by the client.
Before Cisco IOS Release 12.2(25)SE, the switch did not maintain the EAPOL packet history and allowed clients that failed authentication access to the guest VLAN, regardless of whether EAPOL packets had been detected on the interface. You can use the dot1x guest-vlan supplicant global configuration command to enable this optional behavior.
With Cisco IOS Release 12.2(25)SE and later, the switch maintains the EAPOL packet history. If another EAPOL packet is detected on the interface during the lifetime of the link, network access is denied. The EAPOL history is reset upon loss of link.
Any number of non-802.1x-capable clients are allowed access when the switch port is moved to the guest VLAN. If an 802.1x-capable client joins the same port on which the guest VLAN is configured, the port is put into the unauthorized state in the user-configured access VLAN, and authentication is restarted.
Guest VLANs are supported on 802.1x ports in single-host or multiple-hosts mode.
You can configure any active VLAN except an RSPAN VLAN, private VLAN, or a voice VLAN as an 802.1x guest VLAN. The guest VLAN feature is not supported on internal VLANs (routed ports) or trunk ports; it is supported only on access ports.
After you configure a guest VLAN for an 802.1x port to which a DHCP client is connected, you might need to get a host IP address from a DHCP server. You can also change the settings for restarting the 802.1x authentication process on the switch before the DHCP process on the client times out and tries to get a host IP address from the DHCP server. Decrease the settings for the 802.1x authentication process (802.1x quiet period and switch-to-client transmission time).
Examples
This example shows how to specify VLAN 5 as an 802.1x guest VLAN:
Switch(config-if)# dot1x guest-vlan 5This example shows how to set 3 as the quiet time on the switch, to set 15 as the number of seconds that the switch waits for a response to an EAP-request/identity frame from the client before resending the request, and to enable VLAN 2 as an 802.1x guest VLAN when an 802.1X port is connected to a DHCP client:
Switch(config-if)# dot1x timeout quiet-period 3Switch(config-if)# dot1x timeout tx-period 15Switch(config-if)# dot1x guest-vlan 2This example shows how to enable the optional guest VLAN behavior and to specify VLAN 5 as an 802.1x guest VLAN:
Switch(config)# dot1x guest-vlan supplicantSwitch(config)# interface gigabitethernet2/0/1Switch(config-if)# dot1x guest-vlan 5You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
Enables the optional guest VLAN supplicant feature.
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x host-mode
Use the dot1x host-mode interface configuration command on the switch stack or on a standalone switch to allow a single host (client) or multiple hosts on an 802.1x-authorized port that has the dot1x port-control interface configuration command set to auto. Use the no form of this command to return to the default setting.
dot1x host-mode {multi-host | single-host}
no dot1x host-mode [multi-host | single-host]
Syntax Description
multi-host
Enable multiple-hosts mode on the switch.
single-host
Enable single-host mode on the switch.
Defaults
The default is single-host mode.
Command Modes
Interface configuration
Command History
12.1(14)EA1
This command was introduced. It replaces the dot1x multiple-hosts interface configuration command.
Usage Guidelines
Use this command to limit an 802.1x-enabled port to a single client or to attach multiple clients to an 802.1x-enabled port. In multiple-hosts mode, only one of the attached hosts must be successfully authorized for all hosts to be granted network access. If the port becomes unauthorized (re-authentication fails or an Extensible Authentication Protocol over LAN [EAPOL]-logoff message is received), all attached clients are denied access to the network.
Before entering this command, make sure that the dot1x port-control interface configuration command is set to auto for the specified port.
Examples
This example shows how to enable 802.1x globally, to enable 802.1x on a port, and to enable multiple-hosts mode:
Switch(config)# dot1x system-auth-controlSwitch(config)# interface gigabitethernet2/0/1Switch(config-if)# dot1x port-control autoSwitch(config-if)# dot1x host-mode multi-hostYou can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x initialize
Use the dot1x initialize privileged EXEC command on the switch stack or on a standalone switch to manually return the specified 802.1x-enabled port to an unauthorized state before initiating a new authentication session on the port.
dot1x initialize interface interface-id
Syntax Description
Defaults
There is no default setting.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Use this command to initialize the 802.1x state machines and to set up a fresh environment for authentication. After you enter this command, the port status becomes unauthorized.
There is no no form of this command.
Examples
This example shows how to manually initialize a port:
Switch# dot1x initialize interface gigabitethernet2/0/2You can verify the unauthorized port status by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x max-reauth-req
Use the dot1x max-reauth-req interface configuration command on the switch stack or on a standalone switch to set the maximum number of times that the switch restarts the authentication process before a port transitions to the unauthorized state. Use the no form of this command to return to the default setting.
dot1x max-reauth-req count
no dot1x max-reauth-req
Syntax Description
count
Number of times that the switch restarts the authentication process before the port transitions to the unauthorized state. The range is 1 to 10.
Defaults
The default is 2 times.
Command Modes
Interface configuration
Command History
Usage Guidelines
You should change the default value of this command only to adjust for unusual circumstances such as unreliable links or specific behavioral problems with certain clients and authentication servers.
Examples
This example shows how to set 4 as the number of times that the switch restarts the authentication process before the port transitions to the unauthorized state:
Switch(config-if)# dot1x max-reauth-req 4You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
Sets the maximum number of times that the switch forwards an EAP-request/identity frame (assuming that no response is received) to the authentication server before restarting the authentication process.
dot1x timeout tx-period
Sets the number of seconds that the switch waits for a response to an EAP-request/identity frame from the client before resending the request.
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x max-req
Use the dot1x max-req interface configuration command on the switch stack or on a standalone switch to set the maximum number of times that the switch sends an Extensible Authentication Protocol (EAP)-request/identity frame (assuming that no response is received) to the client before restarting the authentication process. Use the no form of this command to return to the default setting.
dot1x max-req count
no dot1x max-req
Syntax Description
count
Number of times that the switch sends an EAP-request/identity frame before restarting the authentication process. The range is 1 to 10.
Defaults
The default is 2 times.
Command Modes
Interface configuration
Command History
12.1(11)AX
This command was introduced.
12.1(14)EA1
This command was changed to the interface configuration mode.
Usage Guidelines
You should change the default value of this command only to adjust for unusual circumstances such as unreliable links or specific behavioral problems with certain clients and authentication servers.
Examples
This example shows how to set 5 as the number of times that the switch sends an EAP-request/identity frame before restarting the authentication process:
Switch(config-if)# dot1x max-req 5You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
dot1x timeout tx-period
Sets the number of seconds that the switch waits for a response to an EAP-request/identity frame from the client before resending the request.
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x multiple-hosts
This is an obsolete command.
In past releases, the dot1x multiple-hosts interface configuration command was used on the switch stack or on a standalone switch to allow multiple hosts (clients) on an 802.1x-authorized port.
Command History
12.1(11)AX
This command was introduced.
12.1(14)EA1
The dot1x multiple-hosts interface configuration command was replaced by the dot1x host-mode interface configuration command.
Related Commands
Sets the 802.1x host mode on a port.
Displays 802.1x statistics, administrative status, and operational status for the switch or for the specified port.
dot1x port-control
Use the dot1x port-control interface configuration command on the switch stack or on a standalone switch to enable manual control of the authorization state of the port. Use the no form of this command to return to the default setting.
dot1x port-control {auto | force-authorized | force-unauthorized}
no dot1x port-control
Syntax Description
Defaults
The default is force-authorized.
Command Modes
Interface configuration
Command History
Usage Guidelines
You must globally enable 802.1x on the switch by using the dot1x system-auth-control global configuration command before enabling 802.1x on a specific port.
The 802.1x protocol is supported on Layer 2 static-access ports, voice VLAN ports, and Layer 3 routed ports.
You can use the auto keyword only if the port is not configured as one of these:
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Note
•
To globally disable 802.1x on the switch, use the no dot1x system-auth-control global configuration command. To disable 802.1x on a specific port, use the no dot1x port-control interface configuration command.
Examples
This example shows how to enable 802.1x on a port:
Switch(config)# interface gigabitethernet2/0/1Switch(config-if)# dot1x port-control autoYou can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x re-authenticate
Use the dot1x re-authenticate privileged EXEC command on the switch stack or on a standalone switch to manually initiate a re-authentication of all 802.1x-enabled ports or the specified 802.1x-enabled port.
dot1x re-authenticate interface interface-id
Syntax Description
interface interface-id
Stack switch number, module, and port number of the interface to re-authenticate.
Defaults
There is no default setting.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
You can use this command to re-authenticate a client without waiting for the configured number of seconds between re-authentication attempts (re-authperiod) and automatic re-authentication.
Examples
This example shows how to manually re-authenticate the device connected to a port:
Switch# dot1x re-authenticate interface gigabitethernet2/0/1dot1x re-authentication
This is an obsolete command.
In past releases, the dot1x re-authentication global configuration command was used on the switch stack or on a standalone switch to set the amount of time between periodic re-authentication attempts.
Command History
12.1(11)AX
This command was introduced.
12.1(14)EA1
The dot1x reauthentication interface configuration command replaced the dot1x re-authentication global configuration command.
Related Commands
Sets the number of seconds between re-authentication attempts.
Displays 802.1x statistics, administrative status, and operational status for the switch or for the specified port.
dot1x reauthentication
Use the dot1x reauthentication interface configuration command on the switch stack or on a standalone switch to enable periodic re-authentication of the client. Use the no form of this command to return to the default setting.
dot1x reauthentication
no dot1x reauthentication
Syntax Description
This command has no arguments or keywords.
Defaults
Periodic re-authentication is disabled.
Command Modes
Interface configuration
Command History
12.1(14)EA1
This command was introduced. It replaces the dot1x re-authentication global configuration command (with the hyphen).
Usage Guidelines
You configure the amount of time between periodic re-authentication attempts by using the dot1x timeout reauth-period interface configuration command.
Examples
This example shows how to disable periodic re-authentication of the client:
Switch(config-if)# no dot1x reauthenticationThis example shows how to enable periodic re-authentication and to set the number of seconds between re-authentication attempts to 4000 seconds:
Switch(config-if)# dot1x reauthenticationSwitch(config-if)# dot1x timeout reauth-period 4000You can verify your settings by entering the show dot1x [interface interface-id] privileged EXEC command.
Related Commands
dot1x timeout reauth-period
Sets the number of seconds between re-authentication attempts.
show dot1x [interface interface-id]
Displays 802.1x status for the specified port.
dot1x timeout
Use the dot1x timeout interface configuration command on the switch stack or on a standalone switch to set 802.1x timers. Use the no form of this command to return to the default setting.
dot1x timeout {quiet-period seconds | reauth-period seconds | server-timeout seconds | supp-timeout seconds | tx-period seconds}
no dot1x timeout {quiet-period | reauth-period | server-timeout | supp-timeout | tx-period}
Syntax Description
Defaults
These are the default settings:
reauth-period is 3600 seconds.
quiet-period is 60 seconds.
tx-period is 30 seconds.
supp-timeout is 30 seconds.
server-timeout is 30 seconds.
Command Modes
Interface configuration
Command History
Usage Guidelines
You should change the default value of this command only to adjust for unusual circumstances such as unreliable links or specific behavioral problems with certain clients and authentication servers.
The dot1x timeout reauth-period interface configuration command affects the behavior of the switch only if you have enabled periodic re-authentication by using the dot1x reauthentication interface configuration command.
During the quiet period, the switch does not accept or initiate any authentication requests. If you want to provide a faster response time to the user, enter a smaller number than the default.
Examples
This example shows how to enable periodic re-authentication and to set 4000 as the number of seconds between re-authentication attempts:
Switch(config-if)# dot1x reauthenticationSwitch(config-if)# dot1x timeout reauth-period 4000This example shows how to set 30 seconds as the quiet time on the switch:
Switch(config-if)# dot1x timeout quiet-period 30This example shows how to set 45 seconds as the switch-to-authentication server retransmission time:
Switch(config)# dot1x timeout server-timeout 45This example shows how to set 45 seconds as the switch-to-client retransmission time for the EAP request frame:
Switch(config-if)# dot1x timeout supp-timeout 45This example shows how to set 60 as the number of seconds to wait for a response to an EAP-request/identity frame from the client before re-transmitting the request:
Switch(config-if)# dot1x timeout tx-period 60You can verify your settings by entering the show dot1x privileged EXEC command.
Related Commands
duplex
Use the duplex interface configuration command on the switch stack or on a standalone switch to specify the duplex mode of operation for a port. Use the no form of this command to return the port to its default value.
duplex {auto | full | half}
no duplex
Syntax Description
Defaults
The default is auto for Fast Ethernet and Gigabit Ethernet ports and for 1000BASE-T small form-factor pluggable (SFP) modules.
The default is half for 100BASE-FX MMF SFP modules.
Command Modes
Interface configuration
Command History
Usage Guidelines
This command is not available on SFP module ports unless a 1000BASE-T SFP module or a 100BASE-FX MMF SFP module is in the port. All other SFP modules operate only in full-duplex mode.
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This command is not available on a 10-Gigabit Ethernet interface.
Certain ports can be configured to be either full duplex or half duplex. Applicability of this command depends on the device to which the switch is attached.
For Fast Ethernet ports, setting the port to auto has the same effect as specifying half if the attached device does not autonegotiate the duplex parameter.
For Gigabit Ethernet ports, setting the port to auto has the same effect as specifying full if the attached device does not autonegotiate the duplex parameter.
Note
If both ends of the line support autonegotiation, we highly recommend using the default autonegotiation settings. If one interface supports autonegotiation and the other end does not, configure duplex and speed on both interfaces; do use the auto setting on the supported side.
If the speed is set to auto, the switch negotiates with the device at the other end of the link for the speed setting and then forces the speed setting to the negotiated value. The duplex setting remains as configured on each end of the link, which could result in a duplex setting mismatch.
Beginning with Cisco IOS Release 12.2(20)SE1, you can configure the duplex setting when the speed is set to auto.
Caution
Note
Examples
This example shows how to configure an interface for full duplex operation:
Switch(config)# interface gigabitethernet1/0/1Switch(config-if)# duplex fullYou can verify your setting by entering the show interfaces privileged EXEC command.
Related Commands
Displays the interface settings on the switch.
Sets the speed on a 10/100 or 10/100/1000 Mbps interface.
errdisable detect cause
Use the errdisable detect cause global configuration command on the switch stack or on a standalone switch to enable error-disabled detection for a specific cause or all causes. Use the no form of this command to disable the error-disabled detection feature.
errdisable detect cause {all | arp-inspection | dhcp-rate-limit | dtp-flap | gbic-invalid | l2ptguard | link-flap | loopback | pagp-flap}
no errdisable detect cause {all | arp-inspection | dhcp-rate-limit | dtp-flap | gbic-invalid | l2ptguard | link-flap | pagp-flap}
Syntax Description
Defaults
Detection is enabled for all causes.
Command Modes
Global configuration
Command History
Usage Guidelines
A cause (all, dhcp-rate-limit, and so forth) is the reason why the error-disabled state occurred. When a cause is detected on an interface, the interface is placed in an error-disabled state, an operational state that is similar to a link-down state.
If you set a recovery mechanism for the cause by entering the errdisable recovery global configuration command for the cause, the interface is brought out of the error-disabled state and allowed to retry the operation when all causes have timed out. If you do not set a recovery mechanism, you must enter the shutdown and then the no shutdown commands to manually recover an interface from the error-disabled state.
Examples
This example shows how to enable error-disabled detection for the link-flap error-disabled cause:
Switch(config)# errdisable detect cause link-flapYou can verify your setting by entering the show errdisable detect privileged EXEC command.
Related Commands
Displays errdisable detection information.
show interfaces status err-disabled
Displays interface status or a list of interfaces in the error-disabled state.
errdisable recovery
Use the errdisable recovery global configuration command on the switch stack or on a standalone switch to configure the recover mechanism variables. Use the no form of this command to return to the default setting.
errdisable recovery {cause {all | arp-inspection | bpduguard | channel-misconfig | dhcp-rate-limit | dtp-flap | gbic-invalid | l2ptguard | link-flap | loopback | pagp-flap | psecure-violation | security-violation | udld | vmps} | {interval interval}
no errdisable recovery {cause {all | arp-inspection | bpduguard | channel-misconfig | dhcp-rate-limit | dtp-flap | gbic-invalid | l2ptguard | link-flap | loopback | pagp-flap | psecure-violation | security-violation | udld | vmps} | {interval interval}
Syntax Description
Note
Defaults
Recovery is disabled for all causes.
The default recovery interval is 300 seconds.
Command Modes
Global configuration
Command History
Usage Guidelines
A cause (all, bpduguard and so forth) is defined as the reason that the error-disabled state occurred. When a cause is detected on an interface, the interface is placed in error-disabled state, an operational state similar to link-down state. If you do not enable errdisable recovery for the cause, the interface stays in error-disabled state until you enter a shutdown and no shutdown interface configuration command. If you enable the recovery for a cause, the interface is brought out of the error-disabled state and allowed to retry the operation again when all the causes have timed out.
Otherwise, you must enter the shutdown then no shutdown commands to manually recover an interface from the error-disabled state.
Examples
This example shows how to enable the recovery timer for the BPDU guard error-disabled cause:
Switch(config)# errdisable recovery cause bpduguardThis example shows how to set the timer to 500 seconds:
Switch(config)# errdisable recovery interval 500You can verify your settings by entering the show errdisable recovery privileged EXEC command.
Related Commands
Displays errdisable recovery timer information.
show interfaces status err-disabled
Displays interface status or a list of interfaces in error-disabled state.
flowcontrol
Use the flowcontrol interface configuration command on the switch stack or on a standalone switch to set the receive flow-control state for an interface. When flow control send is operable and on for a device and it detects any congestion at its end, it notifies the link partner or the remote device of the congestion by sending a pause frame. When flow control receive is on for a device and it receives a pause frame, it stops sending any data packets. This prevents any loss of data packets during the congestion period.
Use the receive off keywords to disable flow control.
flowcontrol receive {desired | off | on}
Note
Syntax Description
Defaults
The default is flowcontrol receive off.
Command Modes
Interface configuration
Command History
Usage Guidelines
The switch does not support sending flow-control pause frames.
Note that the on and desired keywords have the same result.
When you use the flowcontrol command to set a port to control traffic rates during congestion, you are setting flow control on a port to one of these conditions:
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Table 2-5 shows the flow control results on local and remote ports for a combination of settings. The table assumes that receive desired has the same results as using the receive on keywords.
Examples
This example shows how to configure the local port to not support flow control by the remote port:
Switch(config)# interface gigabitethernet1/0/1Switch(config-if)# flowcontrol receive offYou can verify your settings by entering the show interfaces privileged EXEC command.
Related Commands
Displays the interface settings on the switch, including input and output flow control.
interface port-channel
Use the interface port-channel global configuration command on the switch stack or on a standalone switch to access or create the port-channel logical interface. Use the no form of this command to remove the port-channel.
interface port-channel port-channel-number
no interface port-channel port-channel-number
Syntax Description
Defaults
No port-channel logical interfaces are defined.
Command Modes
Global configuration
Command History
12.1(11)AX
This command was introduced.
12.2(25)SE
The port-channel-number range was changed from 1 to 12 to 1 to 48.
Usage Guidelines
For Layer 2 EtherChannels, you do not have to create a port-channel interface first before assigning a physical port to a channel group. Instead, you can use the channel-group interface configuration command. It automatically creates the port-channel interface when the channel group gets its first physical port. If you create the port-channel interface first, the channel-group-number can be the same as the port-channel-number, or you can use a new number. If you use a new number, the channel-group command dynamically creates a new port channel.
You create Layer 3 port channels by using the interface port-channel command followed by the no switchport interface configuration command. You should manually configure the port-channel logical interface before putting the interface into the channel group.
Only one port channel in a channel group is allowed.
Caution
Caution
Follow these guidelines when you use the interface port-channel command:
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For a complete list of configuration guidelines, see the "Configuring EtherChannels" chapter in the software configuration guide for this release.
Examples
This example shows how to create a port-channel interface with a port channel number of 5:
Switch(config)# interface port-channel 5You can verify your setting by entering the show running-config privileged EXEC or show etherchannel channel-group-number detail privileged EXEC command.
Related Commands
interface range
Use the interface range global configuration command on the switch stack or on a standalone switch to enter interface range configuration mode and to execute a command on multiple ports at the same time. Use the no form of this command to remove an interface range.
interface range {port-range | macro name}
no interface range {port-range | macro name}
Syntax Description
port-range
Port range. For a list of valid values for port-range, see the "Usage Guidelines" section.
macro name
Specify the name of a macro.
Defaults
This command has no default setting.
Command Modes
Global configuration
Command History
Usage Guidelines
When you enter interface range configuration mode, all interface parameters you enter are attributed to all interfaces within the range.
For VLANs, you can use the interface range command only on existing VLAN switch virtual interfaces (SVIs). To display VLAN SVIs, enter the show running-config privileged EXEC command. VLANs not displayed cannot be used in the interface range command. The commands entered under interface range command are applied to all existing VLAN SVIs in the range.
All configuration changes made to an interface range are saved to NVRAM, but the interface range itself is not saved to NVRAM.
You can enter the interface range in two ways:
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All interfaces in a range must be the same type; that is, all Fast Ethernet ports, all Gigabit Ethernet ports, all EtherChannel ports, or all VLANs. However, you can define up to five interface ranges with a single command, with each range separated by a comma.
Valid values for port-range type and interface:
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For physical interfaces:
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