Table Of Contents
udld (interface configuration)
vmps reconfirm (global configuration)
vmps reconfirm (privileged EXEC)
2traceroute mac
Use the traceroute mac privileged EXEC command to display the Layer 2 path taken by the packets from the specified source MAC address to the specified destination MAC address.
tracetroute mac [interface interface-id] {source-mac-address} [interface interface-id] {destination-mac-address} [vlan vlan-id] [detail]
Syntax Description
Defaults
There is no default.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The Layer 2 traceroute feature is available on these switches:
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Catalyst 2950 switches running Release 12.1(12c)EA1 or later
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For Layer 2 traceroute to functional properly, Cisco Discovery Protocol (CDP) must be enabled on all the switches in the network. Do not disable CDP.
When the switch detects a device in the Layer 2 path that does not support Layer 2 traceroute, the switch continues to send Layer 2 trace queries and lets them time out.
The maximum number of hops identified in the path is ten.
Layer 2 traceroute supports only unicast source and destination MAC addresses. If you specify a multicast source or destination MAC address, the physical path is not identified, and an error message appears.
The traceroute mac command output shows the Layer 2 path when the specified source and destination addresses belong to the same VLAN. If you specify source and destination addresses that belong to different VLANs, the Layer 2 path is not identified, and an error message appears.
If the source or destination MAC address belongs to multiple VLANs, you must specify the VLAN to which both the source and destination MAC addresses belong. If the VLAN is not specified, the path is not identified, and an error message appears.
The Layer 2 traceroute feature is not supported when multiple devices are attached to one port through hubs (for example, multiple CDP neighbors are detected on a port). When more than one CDP neighbor is detected on a port, the Layer 2 path is not identified, and an error message appears.
This feature is not supported in Token Ring VLANs.
Examples
This example shows how to display the Layer 2 path by specifying the source and destination MAC addresses:
Switch# traceroute mac 0000.0201.0601 0000.0201.0201Source 0000.0201.0601 found on con6[WS-C2950G-24-EI] (2.2.6.6)con6 (2.2.6.6) :Fa0/1 => Fa0/3con5 (2.2.5.5 ) : Fa0/3 => Gi0/1con1 (2.2.1.1 ) : Gi0/1 => Gi0/2con2 (2.2.2.2 ) : Gi0/2 => Fa0/1Destination 0000.0201.0201 found on con2[WS-C3550-24] (2.2.2.2)Layer 2 trace completedThis example shows how to display the Layer 2 path by using the detail keyword:
Switch# traceroute mac 0000.0201.0601 0000.0201.0201 detailSource 0000.0201.0601 found on con6[WS-C2950G-24-EI] (2.2.6.6)con6 / WS-C2950G-24-EI / 2.2.6.6 :Fa0/1 [auto, auto] => Fa0/3 [auto, auto]con5 / WS-C2950G-24-EI / 2.2.5.5 :Fa0/3 [auto, auto] => Gi0/1 [auto, auto]con1 / WS-C3550-12G / 2.2.1.1 :Gi0/1 [auto, auto] => Gi0/2 [auto, auto]con2 / WS-C3550-24 / 2.2.2.2 :Gi0/2 [auto, auto] => Fa0/1 [auto, auto]Destination 0000.0201.0201 found on con2[WS-C3550-24] (2.2.2.2)Layer 2 trace completed.This example shows how to display the Layer 2 path by specifying the interfaces on the source and destination switches:
Switch# traceroute mac interface fastethernet0/1 0000.0201.0601 interface fastethernet0/3 0000.0201.0201Source 0000.0201.0601 found on con6[WS-C2950G-24-EI] (2.2.6.6)con6 (2.2.6.6) :Fa0/1 => Fa0/3con5 (2.2.5.5 ) : Fa0/3 => Gi0/1con1 (2.2.1.1 ) : Gi0/1 => Gi0/2con2 (2.2.2.2 ) : Gi0/2 => Fa0/1Destination 0000.0201.0201 found on con2[WS-C3550-24] (2.2.2.2)Layer 2 trace completedThis example shows the Layer 2 path when the switch is not connected to the source switch:
Switch# traceroute mac 0000.0201.0501 0000.0201.0201 detailSource not directly connected, tracing source .....Source 0000.0201.0501 found on con5[WS-C2950G-24-EI] (2.2.5.5)con5 / WS-C2950G-24-EI / 2.2.5.5 :Fa0/1 [auto, auto] => Gi0/1 [auto, auto]con1 / WS-C3550-12G / 2.2.1.1 :Gi0/1 [auto, auto] => Gi0/2 [auto, auto]con2 / WS-C3550-24 / 2.2.2.2 :Gi0/2 [auto, auto] => Fa0/1 [auto, auto]Destination 0000.0201.0201 found on con2[WS-C3550-24] (2.2.2.2)Layer 2 trace completed.This example shows the Layer 2 path when the switch cannot find the destination port for the source MAC address:
Switch# traceroute mac 0000.0011.1111 0000.0201.0201Error:Source Mac address not found.Layer2 trace aborted.This example shows the Layer 2 path when the source and destination devices are in different VLANs:
Switch# traceroute mac 0000.0201.0601 0000.0301.0201Error:Source and destination macs are on different vlans.Layer2 trace aborted.This example shows the Layer 2 path when the destination MAC address is a multicast address:
Switch# traceroute mac 0000.0201.0601 0100.0201.0201Invalid destination mac addressThis example shows the Layer 2 path when source and destination switches belong to multiple VLANs:
Switch# traceroute mac 0000.0201.0601 0000.0201.0201Error:Mac found on multiple vlans.Layer2 trace aborted.Related Commands
Displays the Layer 2 path taken by the packets from the specified source IP address or hostname to the specified destination IP address or hostname.
traceroute mac ip
Use the traceroute mac privileged EXEC command to display the Layer 2 path taken by the packets from the specified source IP address or hostname to the specified destination IP address or hostname.
tracetroute mac ip {source-ip-address | source-hostname} {destination-ip-address | destination-hostname} [detail]
Syntax Description
Defaults
There is no default.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
The Layer 2 traceroute feature is available on these switches:
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For Layer 2 traceroute to functional properly, Cisco Discovery Protocol (CDP) must be enabled on all the switches in the network. Do not disable CDP.
When the switch detects an device in the Layer 2 path that does not support Layer 2 traceroute, the switch continues to send Layer 2 trace queries and lets them time out.
The maximum number of hops identified in the path is ten.
The traceroute mac ip command output shows the Layer 2 path when the specified source and destination IP addresses are in the same subnet. When you specify the IP addresses, the switch uses Address Resolution Protocol (ARP) to associate the IP addresses with the corresponding MAC addresses and the VLAN IDs.
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The Layer 2 traceroute feature is not supported when multiple devices are attached to one port through hubs (for example, multiple CDP neighbors are detected on a port). When more than one CDP neighbor is detected on a port, the Layer 2 path is not identified, and an error message appears.
This feature is not supported in Token Ring VLANs.
Examples
This example shows how to display the Layer 2 path by specifying the source and destination IP addresses and by using the detail keyword:
Switch# traceroute mac ip 2.2.66.66 2.2.22.22 detailTranslating IP to mac .....2.2.66.66 => 0000.0201.06012.2.22.22 => 0000.0201.0201Source 0000.0201.0601 found on con6[WS-C2950G-24-EI] (2.2.6.6)con6 / WS-C2950G-24-EI / 2.2.6.6 :Fa0/1 [auto, auto] => Fa0/3 [auto, auto]con5 / WS-C2950G-24-EI / 2.2.5.5 :Fa0/3 [auto, auto] => Gi0/1 [auto, auto]con1 / WS-C3550-12G / 2.2.1.1 :Gi0/1 [auto, auto] => Gi0/2 [auto, auto]con2 / WS-C3550-24 / 2.2.2.2 :Gi0/2 [auto, auto] => Fa0/1 [auto, auto]Destination 0000.0201.0201 found on con2[WS-C3550-24] (2.2.2.2)Layer 2 trace completed.This example shows how to display the Layer 2 path by specifying the source and destination hostnames:
Switch# traceroute mac ip con6 con2Translating IP to mac .....2.2.66.66 => 0000.0201.06012.2.22.22 => 0000.0201.0201Source 0000.0201.0601 found on con6con6 (2.2.6.6) :Fa0/1 => Fa0/3con5 (2.2.5.5 ) : Fa0/3 => Gi0/1con1 (2.2.1.1 ) : Gi0/1 => Gi0/2con2 (2.2.2.2 ) : Gi0/2 => Fa0/1Destination 0000.0201.0201 found on con2Layer 2 trace completedThis example shows the Layer 2 path when ARP cannot associate the source IP address with the corresponding MAC address:
Switch# traceroute mac ip 2.2.66.66 2.2.77.77Arp failed for destination 2.2.77.77.Layer2 trace aborted.Related Commands
Displays the Layer 2 path taken by the packets from the specified source MAC address to the specified destination MAC address.
udld (global configuration)
Use the udld global configuration command to enable aggressive or normal mode in the UniDirectional Link Detection (UDLD) and to set the configurable message timer. Use the no form of this command to disable aggressive or normal mode UDLD on all fiber-optic ports.
udld {aggressive | enable | message time message-timer-interval}
no udld {aggressive | enable | message time}
Syntax Description
Defaults
UDLD is disabled on all fiber-optic interfaces.
The message timer is set at 60 seconds.
Command Modes
Global configuration
Command History
12.0(5.2)WC(1)
This command was first introduced.
12.1(6)EA2
The udld enable global configuration command was changed to udld (global configuration).
Usage Guidelines
Use the udld global configuration command to enable UDLD only on fiber-optic ports.
In normal mode, if UDLD is in the advertisement or in the detection phase and all the neighbor cache entries are aged out, UDLD restarts the link-up sequence to resynchronize with any potentially out-of-sync neighbors.
If you enable aggressive mode, when all the neighbors of a port have aged out either in the advertisement or in the detection phase, UDLD restarts the link-up sequence to resynchronize with any potentially out-of-sync neighbor. UDLD shuts down the port if, after the fast train of messages, the link state is still undetermined. Use aggressive mode on point-to-point links where no failure between two neighbors is allowed. In this situation, UDLD probe packets can be considered as a heart beat whose presence guarantees the health of the link. Conversely, the loss of the heart beat means that the link must be shut down if it is not possible to re-establish a bidirectional link.
If you change the message time between probe packets, you are making a trade-off between the detection speed and the CPU load. By decreasing the time, you can make the detection-response faster but increase the load on the CPU.
This command affects fiber-optic interfaces only. Use the udld interface configuration command to enable UDLD on other interface types.
Examples
This example shows how to enable UDLD on all fiber-optic interfaces:
Switch(config)# udld enableYou can verify your settings by entering the show udld privileged EXEC command.
Related Commands
udld (interface configuration)
Use the udld interface configuration command to enable UniDirectional Link Detection (UDLD) on an individual interface or to prevent a fiber-optic interface from being enabled by the udld global configuration command. Use the no form of this command to return to the udld global configuration command setting or disable UDLD if entered on a nonfiber-optic port.
udld {aggressive | enable | disable}
no udld {aggressive | enable | disable}
Syntax Description
Defaults
On fiber-optic interfaces, UDLD is not enabled, in aggressive mode, or disabled. For this reason, fiber-optic interfaces enable UDLD according to the state of the udld enable or udld aggressive global configuration command.
On nonfiber-optic interfaces, UDLD is disabled.
Command Modes
Interface configuration
Command History
12.0(5.2)WC(1)
This command was first introduced.
12.1(6)EA2
The aggressive keyword was added.
Usage Guidelines
UDLD is supported on fiber- and copper-based Ethernet ports.
A UDLD-capable port cannot detect a unidirectional link if it is connected to a UDLD-incapable port of another switch.
This setting overrides the global UDLD configuration on the switch.
In normal mode, if UDLD is in the advertisement or in the detection phase and all the neighbor cache entries are aged out, UDLD restarts the link-up sequence to resynchronize with any potentially out-of-sync neighbors.
If you enable aggressive mode, when all the neighbors of a port have aged out either in the advertisement or in the detection phase, UDLD restarts the link-up sequence to resynchronize with any potentially out-of-sync neighbor. UDLD shuts down the port if, after the fast train of messages, the link state is still undetermined. Use aggressive mode on point-to-point links where no failure between two neighbors is allowed. In this situation, UDLD probe packets can be considered as a heart beat whose presence guarantees the health of the link. Conversely, the loss of the heart beat means that the link must be shut down if it is not possible to re-establish a bidirectional link.
Use the no udld enable command on fiber-optic ports to return control of UDLD to the udld enable global configuration command or to disable UDLD on nonfiber-optic ports.
Use the udld aggressive command on fiber-optic ports to override the settings of the udld enable or udld aggressive global configuration command. Use the no form on fiber-optic ports to remove this setting and to return control of UDLD enabling to the udld global configuration command or to disable UDLD on nonfiber-optic ports.
The disable keyword is supported on fiber-optic ports only. Use the no form of this command to remove this setting and to return control of UDLD to the udld global configuration command.
If the switch software detects a GBIC module change and the interface changes from fiber optic to nonfiber optic or from nonfiber optic to fiber optic, all configurations are maintained.
Examples
This example shows how to enable UDLD on an interface:
Switch(config)# interface fastethernet0/2Switch(config-if)# udld enableThis example shows how to disable UDLD on a fiber-optic interface despite the setting of the udld global configuration command:
Switch(config)# interface gigabitethernet0/2Switch(config-if)# udld disableYou can verify your settings by entering the show running-config or show udld privileged EXEC command.
Related Commands
udld reset
Use the udld reset privileged EXEC command to reset all interfaces shut down by UniDirectional Link Detection (UDLD) and to permit traffic to again pass through. Other features, such as spanning tree, Port Aggregation Protocol (PAgP), and Dynamic Trunking Protocol (DTP), still have their normal effects, if enabled.
udld reset
Syntax Description
This command has no keywords or arguments.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
If the interface configuration is still enabled for UDLD, these ports begin to run UDLD again and might shut down for the same reason if the problem has not been corrected.
Examples
This example shows how to reset all interfaces that have been shut down by UDLD:
Switch# udld reset1 ports shutdown by UDLD were reset.You can verify your settings by entering the show udld privileged EXEC command.
Related Commands
vlan (global configuration)
Use the vlan global configuration command to add a VLAN and enter the config-vlan mode. Use the no form of this command to delete the VLAN. Configuration information for normal-range VLANs (VLAN IDs 1 to 1005) is always saved in the VLAN database. When VLAN Trunking Protocol (VTP) mode is transparent, you can create extended-range VLANs (VLAN IDs greater than 1005), and the VTP mode and domain name and the VLAN configuration are saved in the switch running configuration file. You can save configurations in the switch startup configuration file by entering the copy running-config startup-config privileged EXEC command.
vlan vlan-id
no vlan vlan-id
Syntax Description
Defaults
This command has no default settings.
Command Modes
Global configuration
Command History
12.1(9)EA1
This command was first introduced.
12.1(11)EA1
The remote-span configuration command was added.
Usage Guidelines
You must use the vlan vlan-id global configuration command to add extended-range VLANs (VLAN IDs 1006 to 4094). Before configuring VLANs in the extended range, you must use the vtp transparent global configuration or VLAN configuration command to put the switch in VTP transparent mode. Extended-range VLANs are not learned by VTP and are not added to the VLAN database, but when VTP mode is transparent, VTP mode and domain name and all VLAN configurations are saved in the running configuration, and you can save them in the switch startup configuration file.
When you save the VLAN and VTP configurations in the startup configuration file and reboot the switch, the configuration is determined in these ways:
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If you try to create an extended-range VLAN when the switch is not in VTP transparent mode, the VLAN is rejected, and you receive an error message.
If you enter an invalid VLAN ID, you receive an error message and do not enter config-vlan mode.
Entering the vlan command with a VLAN ID enables config-vlan mode. When you enter the VLAN ID of an existing VLAN, you do not create a new VLAN, but you can modify VLAN parameters for that VLAN. The specified VLANs are added or modified when you exit the config-vlan mode. Only the shutdown command (for VLANs 1 to 1005) takes effect immediately.
These configuration commands are available in config-vlan mode. The no form of each command returns the characteristic to its default state.
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Table 2-23 describes the rules for configuring VLANs.
Examples
This example shows how to add an Ethernet VLAN with default media characteristics. The default includes a vlan-name of VLANxxx, where xxxx represents four numeric digits (including leading zeros) equal to the VLAN ID number. The default media option is ethernet; the state option is active. The default said-value variable is 100000 plus the VLAN ID; the mtu-size variable is 1500; the stp-type option is ieee. When you enter the exit config-vlan configuration command, the VLAN is added if it did not already exist; otherwise, this command does nothing.
This example shows how to create a new VLAN with all default characteristics and enter config-vlan mode:
Switch(config)# vlan 200Switch(config-vlan)# exitSwitch(config)#This example shows how to create a new extended-range VLAN (when the EI is installed) with all the default characteristics, to enter config-vlan mode, and to save the new VLAN in the switch startup configuration file:
Switch(config)# vtp mode transparentSwitch(config)# vlan 2000Switch(config-vlan)# endSwitch# copy running-config startup configYou can verify your setting by entering the show vlan privileged EXEC command.
Related Commands
vlan (VLAN configuration)
Use the vlan VLAN configuration command to configure VLAN characteristics for a normal-range VLAN (VLAN IDs 1 to 1005) in the VLAN database. You access VLAN configuration mode by entering the vlan database privileged EXEC command. Use the no form of this command without additional parameters to delete a VLAN. Use the no form with parameters to change its configured characteristics.
vlan vlan-id [are are-number] [backupcrf {enable | disable}] [bridge bridge-number |
type {srb | srt}] [media {ethernet | fddi | fdi-net | tokenring | tr-net}] [mtu mtu-size]
[name vlan-name] [parent parent-vlan-id] [ring ring-number] [said said-value]
[state {suspend | active}] [ste ste-number] [stp type {ieee | ibm | auto}]
[tb-vlan1 tb-vlan1-id] [tb-vlan2 tb-vlan2-id]no vlan vlan-id [are are-number] [backupcrf {enable | disable}] [bridge bridge-number |
type {srb | srt}] [media {ethernet | fddi | fdi-net | tokenring | tr-net}] [mtu mtu-size]
[name vlan-name] [parent parent-vlan-id] [ring ring-number] [said said-value]
[state {suspend | active}] [ste ste-number] [stp type {ieee | ibm | auto}]
[tb-vlan1 tb-vlan1-id] [tb-vlan2 tb-vlan2-id]Extended-range VLANs (with VLAN IDs from 1006 to 4094) cannot be added or modified by using these commands. To add extended-range VLANs, use the vlan (global configuration) command to enter config-vlan mode.
Note
Syntax Description
vlan-id
ID of the configured VLAN. Valid IDs are from 1 to 1005 and must be unique within the administrative domain. Do not enter leading zeros.
are are-number
(Optional) Specify the maximum number of all-routes explorer (ARE) hops for this VLAN. This keyword applies only to TrCRF VLANs. Valid values are from 0 to 13. If no value is entered, 0 is assumed to be the maximum.
backupcrf {enable | disable}
(Optional) Specify the backup CRF mode. This keyword applies only to TrCRF VLANs.
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bridge bridge-number|
type {srb | srt}(Optional) Specify the logical distributed source-routing bridge, the bridge that interconnects all logical rings having this VLAN as a parent VLAN in FDDI-NET, Token Ring-NET, and TrBRF VLANs.
Valid bridge numbers are from 0 to 15.
The type keyword applies only to TrCRF VLANs and is one of these:
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media {ethernet | fddi | fd-net | tokenring | tr-net}
(Optional) Specify the VLAN media type. Table 2-24 lists the valid syntax for each media type.
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mtu mtu-size
(Optional) Specify the maximum transmission unit (MTU) (packet size in bytes). Valid values are from 1500 to 18190.
name vlan-name
(Optional) Specify the VLAN name, an ASCII string from 1 to 32 characters that must be unique within the administrative domain.
parent parent-vlan-id
(Optional) Specify the parent VLAN of an existing FDDI, Token Ring, or TrCRF VLAN. This parameter identifies the TrBRF to which a TrCRF belongs and is required when defining a TrCRF. Valid values are from 0 to 1005.
ring ring-number
(Optional) Specify the logical ring for an FDDI, Token Ring, or TrCRF VLAN. Valid values are from 1 to 4095.
said said-value
(Optional) Enter the security association identifier (SAID) as documented in IEEE 802.10. The value is an integer from 1 to 4294967294 that must be unique within the administrative domain.
state {suspend | active}
(Optional) Specify the VLAN state:
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ste ste-number
(Optional) Specify the maximum number of spanning-tree explorer (STE) hops. This keyword applies only to TrCRF VLANs. Valid values are from 0 to 13.
stp type {ieee | ibm | auto}
(Optional) Specify the spanning-tree type for FDDI-NET, Token Ring-NET, or TrBRF VLAN.
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tb-vlan1 tb-vlan1-id
and tb-vlan2 tb-vlan2-id
(Optional) Specify the first and second VLAN to which this VLAN is translationally bridged. Translational VLANs translate FDDI or Token Ring to Ethernet, for example. Valid values are from 0 to 1005. Zero is assumed if no value is specified.
Table 2-24 shows the valid syntax options for different media types.
Table 2-25 describes the rules for configuring VLANs.
Defaults
The ARE value is 7.
Backup CRF is disabled.
The bridge number is 0 (no source-routing bridge) for FDDI-NET, TrBRF, and Token Ring-NET VLANs.
The media type is ethernet.
The default mtu size is 1500 bytes.
The vlan-name variable is VLANxxxx, where xxxx represents four numeric digits (including leading zeros) equal to the VLAN ID number.
The parent VLAN ID is 0 (no parent VLAN) for FDDI and Token Ring VLANs. For TrCRF VLANs, you must specify a parent VLAN ID. For both Token Ring and TrCRF VLANs, the parent VLAN ID must already exist in the database and be associated with a Token Ring-NET or TrBRF VLAN.
The ring number for Token Ring VLANs is 0. For FDDI VLANs, there is no default.
The said value is 100000 plus the VLAN ID.
The state is active.
The STE value is 7.
The STP type is ieee for FDDI-NET and ibm for Token Ring-NET VLANs. For FDDI and Token Ring VLANs, the default is no type specified.
The tb-vlan1-id and tb-vlan2-id variables are zero (no translational bridging).
Command Modes
VLAN configuration
Command History
Usage Guidelines
You can only use this command mode for configuring normal-range VLANs, that is, VLAN IDs 1 to 1005.
Note
VLAN configuration is always saved in the VLAN database. If VTP mode is transparent, it is also saved in the switch running configuration file, along with the VTP mode and domain name. You can then save it in the switch startup configuration file by using the copy running-config startup-config privileged EXEC command.
When you save VLAN and VTP configuration in the startup configuration file and reboot the switch, the configuration is determined in these ways:
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The following are the results of using the no vlan commands:
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Examples
This example shows how to add an Ethernet VLAN with default media characteristics. The default includes a vlan-name of VLANxxx, where xxxx represents four numeric digits (including leading zeros) equal to the VLAN ID number. The default media option is ethernet; the state option is active. The default said-value variable is 100000 plus the VLAN ID; the mtu-size variable is 1500; the stp-type option is ieee. When you enter the exit or apply vlan configuration command, the VLAN is added if it did not already exist; otherwise, this command does nothing.
Switch(vlan)# vlan 2VLAN 2 added:Name: VLAN0002Switch(vlan)# exitAPPLY completed.Exiting....This example shows how to modify an existing VLAN by changing its name and MTU size:
Switch(vlan)# no vlan name engineering mtu 1200You can verify your settings by entering the show vlan privileged EXEC command.
Related Commands
vlan database
Use the vlan database privileged EXEC command to enter VLAN configuration mode. From this mode, you can add, delete, and modify VLAN configurations for normal-range VLANs and globally propagate these changes by using the VLAN Trunking Protocol (VTP). Configuration information is saved in the VLAN database.
vlan database
Note
Syntax Description
This command has no arguments or keywords.
Defaults
No default is defined.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
You can use the VLAN database configuration commands to configure VLANs 1 to 1005. To configure extended-range VLANs (VLAN IDs 1006 to 4094) (when the enhanced software image (EI) is installed), use the vlan (global configuration) command to enter config-vlan mode. You can also configure VLAN IDs 1 to 1005 by using the vlan global configuration command.
To return to the privileged EXEC mode from the VLAN configuration mode, enter the exit command.
Note
Once you are in VLAN configuration mode, you can access the VLAN database and make changes by using these commands:
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When you have modified VLAN or VTP parameters, you can use these editing buffer manipulation commands:
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You can verify that VLAN database changes have been made or aborted by using the show vlan privileged EXEC command. This output is different from the show VLAN database configuration command output.
Examples
This example shows how to enter the VLAN configuration mode from the privileged EXEC mode and to display VLAN database information:
Switch# vlan databaseSwitch(vlan)# showName: defaultMedia Type: EthernetVLAN 802.10 Id: 100001State: OperationalMTU: 1500Translational Bridged VLAN: 1002Translational Bridged VLAN: 1003Name: VLAN0002Media Type: EthernetVLAN 802.10 Id: 100002State: OperationalMTU: 1500Name: fddi-defaultMedia Type: FDDIVLAN 802.10 Id: 101002State: OperationalMTU: 1500Bridge Type: SRBRing Number: 0Translational Bridged VLAN: 1Translational Bridged VLAN: 1003<output truncated>This is an example of output from the show changes command:
Switch(vlan)# show changesDELETED:Name: VLAN0004Media Type: EthernetVLAN 802.10 Id: 100004State: OperationalMTU: 1500DELETED:Name: VLAN0006Media Type: EthernetVLAN 802.10 Id: 100006State: OperationalMTU: 1500MODIFIED:Current State: OperationalModified State: SuspendedThis example shows how to display the differences between VLAN 7 in the current database and the proposed database.
Switch(vlan)# show changes 7MODIFIED:Current State: OperationalModified State: SuspendedThis is an example of output from the show current 20 command. It displays only VLAN 20 of the current database.
Switch(vlan)# show current 20Name: VLAN0020Media Type: EthernetVLAN 802.10 Id: 100020State: OperationalMTU: 1500Related Commands
vmps reconfirm (global configuration)
Use the vmps reconfirm global configuration command to change the reconfirmation interval for the VLAN Query Protocol (VQP) client.
vmps reconfirm interval
Syntax Description
interval
Reconfirmation interval for VQP client queries to the VLAN Membership Policy Server (VMPS) to reconfirm dynamic VLAN assignments. The interval range is from 1 to 120 minutes.
Defaults
The default reconfirmation interval is 60 minutes.
Command Modes
Global configuration
Command History
Examples
This example shows how to set the VQP client to reconfirm dynamic VLAN entries every 20 minutes:
Switch(config)# vmps reconfirm 20You can verify your settings by entering the show vmps privileged EXEC command and examining information in the Reconfirm Interval row.
Related Commands
Displays VQP and VMPS information.
Sends VQP queries to reconfirm all dynamic VLAN assignments with the VMPS.
vmps reconfirm (privileged EXEC)
Use the vmps reconfirm privileged EXEC command to immediately send VLAN Query Protocol (VQP) queries to reconfirm all dynamic VLAN assignments with the VLAN Membership Policy Server (VMPS).
vmps reconfirm
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 send VQP queries to the VMPS:
Switch# vmps reconfirmYou can verify your settings by entering the show vmps privileged EXEC command and examining the VMPS Action row of the Reconfirmation Status section. The show vmps command shows the result of the last time the assignments were reconfirmed either as a result of the reconfirmation timer expired or because the vmps reconfirm command was entered.
Related Commands
Displays VQP and VMPS information.
Changes the reconfirmation interval for the VLAN Query Protocol (VQP) client.
vmps retry
Use the vmps retry global configuration command to configure the per-server retry count for the VLAN Query Protocol (VQP) client.
vmps retry count
Syntax Description
count
Number of attempts to contact the VLAN Membership Policy Server (VMPS) by the client before querying the next server in the list. The retry range is from 1 to 10.
Defaults
The default retry count is 3.
Command Modes
Global configuration
Command History
Examples
This example shows how to set the retry count to 7:
Switch(config)# vmps retry 7You can verify your settings by entering the show vmps privileged EXEC command and examining information in the Server Retry Count row.
Related Commands
vmps server
Use the vmps server global configuration command to configure the primary VLAN Membership Policy Server (VMPS) and up to three secondary servers. Use the no form of this command to remove a VMPS server.
vmps server ipaddress [primary]
no vmps server [ipaddress]
Syntax Description
Defaults
No primary or secondary VMPS servers are defined.
Command Modes
Global configuration
Command History
Usage Guidelines
The first server entered is automatically selected as the primary server whether or not the primary keyword is entered. The first server address can be overridden by using primary in a subsequent command.
If a member switch in a cluster configuration does not have an IP address, the cluster does not use the VMPS server configured for that member switch. Instead, the cluster uses the VMPS server on the command switch, and the command switch proxies the VMPS requests. The VMPS server treats the cluster as a single switch and uses the IP address of the command switch to respond to requests.
When using the no form without specifying the ipaddress, all configured servers are deleted. If you delete all servers when dynamic-access ports are present, the switch cannot forward packets from new sources on these ports because it cannot query the VMPS.
Examples
This example shows how to configure the server with IP address 191.10.49.20 as the primary VMPS server. The servers with IP addresses 191.10.49.21 and 191.10.49.22 are configured as secondary servers.
Switch(config)# vmps server 191.10.49.20 primarySwitch(config)# vmps server 191.10.49.21Switch(config)# vmps server 191.10.49.22This example shows how to delete the server with IP address 191.10.49.21:
Switch(config)# no vmps server 191.10.49.21You can verify your settings by entering the show vmps privileged EXEC command and examining information in the VMPS Domain Server row.
Related Commands
vtp (global configuration)
Use the vtp global configuration command to set or modify the VLAN Trunking Protocol (VTP) configuration characteristics. Use the no form of this command to remove the settings or to return to the default settings.
vtp {domain domain-name | file filename | interface name | mode {client | server | transparent} | password password | pruning | version number}
no vtp {file | interface | mode | password | pruning | version }
Syntax Description
Defaults
The default filename is flash:vlan.dat.
The default mode is server mode.
No domain name or password is defined.
No password is configured.
Pruning is disabled.
The default version is version 1.
Command Modes
Global configuration
Command History
12.1(9)EA1
The domain and mode keywords were added. The if-id keyword was replaced by the interface keyword.
12.1(11)EA1
The password, pruning, and version keywords were added.
Usage Guidelines
When you save VTP mode and domain name and VLAN configurations in the switch startup configuration file and reboot the switch, the VTP and VLAN configurations are determined by these conditions:
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The vtp file filename cannot be used to load a new database; it renames only the file in which the existing database is stored.
Follow these guidelines when configuring a VTP domain name:
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Follow these guidelines when setting VTP mode:
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Follow these guidelines when setting a VTP password:
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Follow these guidelines when setting VTP pruning:
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Follow these guidelines when setting the VTP version:
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You cannot save password, pruning, and version configurations in the switch configuration file.
Examples
This example shows how to rename the filename for VTP configuration storage to vtpfilename:
Switch(config)# vtp file vtpfilenameThis example shows how to clear the device storage filename:
Switch(config)# no vtp file vtpconfigClearing device storage filename.This example shows how to specify the name of the interface providing the VTP updater ID for this device:
Switch(config)# vtp interface fastethernetThis example shows how to set the administrative domain for the switch:
Switch(config)# vtp domain OurDomainNameThis example shows how to place the switch in VTP transparent mode:
Switch(config)# vtp mode transparentThis example shows how to configure the VTP domain password:
Switch(config)# vtp password ThisIsOurDomain'sPasswordThis example shows how to enable pruning in the VLAN database:
Switch(config)# vtp pruningPruning switched ONThis example shows how to enable version 2 mode in the VLAN database:
Switch(config)# vtp version 2You can verify your settings by entering the show vtp status privileged EXEC command.
Related Commands
show vtp status
Displays the VTP statistics for the switch and general information about the VTP management domain status.
Configures most VTP characteristics.
vtp (privileged EXEC)
Use the vtp privileged EXEC command to configure the VLAN Trunking Protocol (VTP) password, pruning, and version. Use the no form of this command to return to the default settings.
vtp {password password | pruning | version number}
no vtp {password | pruning | version}
Note
Syntax Description
Defaults
No password is configured.
Pruning is disabled.
The default version is version 1.
Command Modes
Privileged EXEC
Command History
Usage Guidelines
Passwords are case sensitive. Passwords should match on all switches in the same domain.
When you use the no vtp password form of the command, the switch returns to the no-password state.
VTP pruning removes information about each pruning-eligible VLAN from VTP updates if there are no stations belonging to that VLAN.
If you enable pruning on the VTP server, it is enabled for the entire management domain for VLAN IDs 1 to 1005.
Only VLANs in the pruning-eligible list can be pruned.
Pruning is supported with VTP version 1 and version 2.
Toggling the version 2 (v2) mode state modifies parameters of certain default VLANs.
Each VTP switch automatically detects the capabilities of all the other VTP devices. To use version 2, all VTP switches in the network must support version 2; otherwise, you must configure them to operate in VTP version 1 mode.
If all switches in a domain are VTP version 2-capable, you need only to configure version 2 on one switch; the version number is then propagated to the other version-2 capable switches in the VTP domain.
If you are using VTP in a Token Ring environment, VTP version 2 must be enabled.
If you are configuring a Token Ring bridge relay function (TrBRF) or Token Ring concentrator relay function (TrCRF) VLAN media type, you must use version 2.
If you are configuring a Token Ring or Token Ring-NET VLAN media type, you must use version 1.
You cannot save password, pruning, and version configuration in the switch configuration file.
Examples
This example shows how to configure the VTP domain password:
Switch# vtp password ThisIsOurDomain'sPasswordThis example shows how to enable pruning in the VLAN database:
Switch# vtp pruningPruning switched ONThis example shows how to enable version 2 mode in the VLAN database:
Switch# vtp version 2You can verify your setting by entering the show vtp status privileged EXEC command.
Related Commands
show vtp status
Displays the VTP statistics for the switch and general information about the VTP management domain status.
switchport trunk pruning
Configures the VLAN pruning-eligible list for ports in trunking mode.
Configures the VTP filename, interface, domain-name, and mode, which can be saved in the switch configuration file.
Configures all VTP characteristics but cannot be saved to the switch configuration file.
vtp (VLAN configuration)
Use the vtp VLAN configuration command to configure VLAN Trunking Protocol (VTP) characteristics. You access VLAN configuration mode by entering the vlan database privileged EXEC command. Use the no form of this command to return to the default settings, disable the characteristic, or remove the password.
vtp {domain domain-name | password password | pruning | v2-mode | {server | client | transparent}}
no vtp {client | password | pruning | transparent | v2-mode}
Note
Syntax Description
Defaults
The default mode is server mode.
No domain name is defined.
No password is configured.
Pruning is disabled.
VTP version 2 (v2 mode) is disabled.
Command Modes
VLAN configuration
Command History
Usage Guidelines
If VTP mode is transparent, the mode and domain name are saved in the switch running configuration file, and you can save the configuration in the switch startup configuration file by using the copy running-config startup-config privileged EXEC command.
Follow these guidelines when setting VTP mode:
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Follow these guidelines when configuring a VTP domain name:
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Follow these guidelines when configuring a VTP password:
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Follow these guidelines when enabling VTP version 2 (v2-mode):
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Examples
This example shows how to place the switch in VTP transparent mode:
Switch(vlan)# vtp transparentSetting device to VTP TRANSPARENT mode.This example shows how to set the administrative domain for the switch:
Switch(vlan)# vtp domain OurDomainNameChanging VTP domain name from cisco to OurDomainNameThis example shows how to configure the VTP domain password:
Switch(vlan)# vtp password privateSetting device VLAN database password to private.This example shows how to enable pruning in the proposed new VLAN database:
Switch(vlan)# vtp pruningPruning switched ONThis example shows how to enable V2 mode in the proposed new VLAN database:
Switch(vlan)# vtp v2-modeV2 mode enabled.You can verify your settings by entering the show vtp status privileged EXEC command.
Related Commands
show vtp status
Displays the VTP statistics for the switch and general information about the VTP management domain status.
switchport trunk pruning
Configures the VLAN pruning-eligible list for ports in trunking mode.
Configures the VTP filename, interface, domain-name, and mode.
wrr-queue bandwidth
Use the wrr-queue bandwidth global configuration command to assign weighted round-robin (WRR) weights to the four class of service (CoS) priority queues. Use the no form of this command to disable the WRR scheduler and enable the strict priority scheduler.
wrr-queue bandwidth weight1...weight4
no wrr-queue bandwidth
Syntax Description
weight1...weight4
The ratio of weight1, weight2, weight3, and weight4 determines the weights of the WRR scheduler. For more information, see the "Usage Guidelines" section.
Defaults
WRR is disabled. The strict priority is the default scheduler.
Command Modes
Global configuration
Command History
12.0(5.2)WC(1)
This command was first introduced.
12.1(12c)EA1
The range for weight4 was modified from 1 to 255 to 0 to 255.
Usage Guidelines
WRR allows bandwidth sharing at the egress port. This command defines the bandwidths for egress WRR by scheduling weights.
For weight1, weight2, and weight3, the range is 1 to 255. The range for weight4 is 0 to 255.
You can configure queues 1, 2, and 3 for WRR scheduling and queue 4 for strict priority. To configure queue 4 as the expedite queue, set weight4 to 0. When queue 4 is empty, packets from queues 1, 2, and 3 are sent according to the assigned WRR weights.
For more information about strict priority and WRR scheduling, refer to the "CoS and WRR" section in the "Configuring Auto-QoS" chapter of the Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide for this release.
Examples
This example shows how to assign WRR weights of 10, 20, 30, and 40 to the CoS priority queues 1, 2, 3, and 4:
Switch(config)# wrr-queue bandwidth 10 20 30 40This example shows how to disable the WRR scheduler and enable the strict priority scheduler:
Switch(config)# no wrr-queue bandwidthThis example shows how to configure queue 4 as the expedite queue and to assign WRR weights of 10, 20, and 30 to the queues 1, 2, and 3:
Switch(config)# wrr-queue bandwidth 10 20 30 0You can verify your settings by entering the show wrr-queue bandwidth privileged EXEC command.
Related Commands
Assigns CoS values to the CoS priority queues.
Displays the WRR bandwidth allocation for the four CoS priority queues.
Displays the mapping of the CoS to the CoS priority queues.
wrr-queue cos-map
Use the wrr-queue cos-map global configuration command to assign class of service (CoS) values to the CoS priority queues. Use the no form of this command to set the CoS map to default setting.
wrr-queue cos-map quid cos1...cosn
no wrr-queue cos-map [queue-id [cos1 ... cosn]]
Syntax Description
quid
The queue id of the CoS priority queue. Ranges are 1 to 4 where 1 is the lowest CoS priority queue.
cos1...cosn
The CoS values that are mapped to the queue id.
Defaults
These are the default CoS values:
Command Modes
Global configuration
Command History
12.0(5.2)WC(1)
This command was first introduced.
12.1(12c)EA1
CoS values were added to the no form of this command.
Usage Guidelines
CoS assigned at the ingress port is used to select a CoS priority at the egress port.
Examples
This example shows how to map CoS values 0, 1, and 2 to CoS priority queue 1, value 3 to CoS priority queue 2, values 4 and 5 to CoS priority 3, and values 6 and 7 to CoS priority queue 4:
Switch(config)# wrr-queue cos-map 1 0 1 2Switch(config)# wrr-queue cos-map 2 3Switch(config)# wrr-queue cos-map 3 4 5Switch(config)# wrr-queue cos-map 4 6 7This example shows how to map CoS values 0, 1, 2, and 3 to CoS priority queue 2:
Switch(config)# wrr-queue cos-map 2 0 1 2 3After entering the wrr-queue cos-map 2 0 1 2 3 command, if all other priority queues use their default setting, this is the new mapping:
In the previous example, CoS priority queue 1 is no longer used because no CoS value is assigned to the queue.
You can set the CoS values to the default values by entering the no wrr-queue cos-map global configuration command.
You can verify your settings by entering the show wrr-queue cos-map privileged EXEC command.
Related Commands
