- Cisco IOS Configuration Fundamentals Command Reference, Release 12.1
Table Of Contents
snmp-server manager session-timeout
snmp-server trap-authentication
SNMP Commands
This chapter describes commands used to configure Simple Network Management Protocol (SNMP) on your routers for the purposes of network monitoring and management.
For SNMP configuration tasks and examples, refer to the "Configuring SNMP Support" chapter in the Release 12.1 Cisco IOS Configuration Fundamentals Configuration Guide.
no snmp-server
To disable Simple Network Management Protocol agent operation, use the no snmp-server command.
no snmp-server
Syntax Description
This command has no arguments or keywords.
Defaults
None
Command Modes
EXEC
Command History
Usage Guidelines
This command disables all running versions of SNMP (SNMPv1, SNMPv2C, SNMPv3) on the device.
Examples
The following example disables the current running version of SNMP:
no snmp-servershow snmp
To check the status of SNMP communications, use the show snmp EXEC command.
show snmp
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Usage Guidelines
This command provides counter information for SNMP operations. It also displays the chassis ID string defined with the snmp-server chassis-id command.
Examples
The following is sample output from the show snmp command:
Router# show snmpChassis: 0150619937 SNMP packets input0 Bad SNMP version errors4 Unknown community name0 Illegal operation for community name supplied0 Encoding errors24 Number of requested variables0 Number of altered variables0 Get-request PDUs28 Get-next PDUs0 Set-request PDUs78 SNMP packets output0 Too big errors (Maximum packet size 1500)0 No such name errors0 Bad values errors0 General errors24 Response PDUs13 Trap PDUsSNMP logging: enabledLogging to 171.69.58.33.162, 0/10, 13 sent, 0 dropped.SNMP Manager-role output packets4 Get-request PDUs4 Get-next PDUs6 Get-bulk PDUs4 Set-request PDUs23 Inform-request PDUs30 Timeouts0 DropsSNMP Manager-role input packets0 Inform response PDUs2 Trap PDUs7 Response PDUs1 Responses with errorsSNMP informs: enabledInforms in flight 0/25 (current/max)Logging to 171.69.217.141.1624 sent, 0 in-flight, 1 retries, 0 failed, 0 droppedLogging to 171.69.58.33.1620 sent, 0 in-flight, 0 retries, 0 failed, 0 droppedTable 39 describes the fields shown in the display.
Related Commands
show snmp engineID
To display the identification of the local Simple Network Management Protocol engine and all remote engines that have been configured on the router, use the show snmp engineID EXEC command.
show snmp engineID
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Usage Guidelines
An SNMP engine is a copy of SNMP that can reside on a local or remote device.
Examples
The following example specifies 00000009020000000C025808 as the local engineID and 123456789ABCDEF000000000 as the remote engine ID, 171.69.37.61 as the IP address of the remote engine, or copy of SNMP, and 162 as the port from which the remote device is connected to the local device:
router# show snmp engineIDLocal SNMP engineID: 00000009020000000C025808Remote Engine ID IP-addr Port123456789ABCDEF000000000 171.69.37.61 162Table 1 describes the fields shown in the example.
Related Commands
snmp-server engineID
Configures a name for either the local or remote SNMP engine on the router.
show snmp group
To display the names of groups on the router and the security model, the status of the different views, and the storage type of each group, use the show snmp group EXEC command.
show snmp group
Syntax Description
This command has no keywords or arguments.
Command Modes
EXEC
Command History
Examples
The following example specifies the group name as public, the security model as v1, the read view name as v1default, the notify view name as *tv.FFFFFFFF, and the storage type as volatile:
router# show snmp groupgroupname: public security model:v1readview:v1defaultwriteview: no writeview specifiednotifyview: *tv.FFFFFFFFstorage-type: volatileTable 41 describes the fields shown in the example.
Related Commands
snmp-server group
Configures a new SNMP group or a table that maps SNMP users to SNMP views.
show snmp pending
To display the current set of pending Simple Network Management Protocol requests, use the show snmp pending EXEC command.
show snmp pending
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Usage Guidelines
After the SNMP manager sends a request, the request is "pending" until the manager receives a response or the request timeout expires.
Examples
The following is sample output from the show snmp pending command:
Router# show snmp pendingreq id: 47, dest: 171.69.58.33.161, V2C community: public, Expires in 5 secsreq id: 49, dest: 171.69.58.33.161, V2C community: public, Expires in 6 secsreq id: 51, dest: 171.69.58.33.161, V2C community: public, Expires in 6 secsreq id: 53, dest: 171.69.58.33.161, V2C community: public, Expires in 8 secsTable 42 describes the fields shown in the display.
Related Commands
Checks the status of SNMP communications.
Displays the current SNMP sessions.
Starts the SNMP manager process.
Sets the amount of time before a nonactive session is destroyed.
show snmp sessions
To display the current SNMP sessions, use the show snmp sessions EXEC command.
show snmp sessions [brief]
Syntax Description
Command Modes
EXEC
Command History
Usage Guidelines
Sessions are created when the SNMP manager in the router sends SNMP requests, such as inform requests, to a host or receives SNMP notifications from a host. One session is created for each destination host. If there is no further communication between the router and host within the session timeout period, the corresponding session will be deleted.
Examples
The following is sample output from the show snmp sessions command:
Router# show snmp sessionsDestination: 171.69.58.33.162, V2C community: publicRound-trip-times: 0/0/0 (min/max/last)packets output0 Gets, 0 GetNexts, 0 GetBulks, 0 Sets, 4 Informs0 Timeouts, 0 Dropspackets input0 Traps, 0 Informs, 0 Responses (0 errors)Destination: 171.69.217.141.162, V2C community: public, Expires in 575 secsRound-trip-times: 1/1/1 (min/max/last)packets output0 Gets, 0 GetNexts, 0 GetBulks, 0 Sets, 4 Informs0 Timeouts, 0 Dropspackets input0 Traps, 0 Informs, 4 Responses (0 errors)The following is sample output from the show snmp sessions brief command:
Router# show snmp sessions briefDestination: 171.69.58.33.161, V2C community: public, Expires in 55 secsTable 43 describes the fields shown in these displays.
Related Commands
show snmp user
To display information on each Simple Network Management Protocol username in the group username table, use the show snmp user EXEC command.
show snmp user
Syntax Description
This command has no arguments or keywords.
Command Modes
EXEC
Command History
Usage Guidelines
An SNMP user is a remote user for which an SNMP management operation is performed. For example, inform operations can be sent to a user on a remote SNMP engine. The user is designated using the snmp-server user command.
Examples
The following example specifies the username as authuser, the engine ID string as 00000009020000000C025808, and the storage-type as nonvolatile:
router# show snmp userUser name: authuserEngine ID: 00000009020000000C025808storage-type: nonvolatileTable 44 describes fields shown in the example.
Related Commands
snmp-server access-policy
This command is no longer valid. The functionality provided by this command has been removed from the Cisco IOS software.
snmp-server chassis-id
To provide a message line identifying the Simple Network Management Protocol server serial number, use the snmp-server chassis-id global configuration command. Use the no form of this command to restore the default value, if any.
snmp-server chassis-id text
no snmp-server chassis-id
Syntax Description
Defaults
On hardware platforms where the serial number can be machine read, the default is the serial number. For example, a Cisco 7000 has a default chassis-id value of its serial number.
Command Modes
Global configuration
Command History
Usage Guidelines
The Cisco MIB provides a chassis MIB variable that enables the SNMP manager to gather data on system card descriptions, chassis type, chassis hardware version, chassis ID string, software version of ROM monitor, software version of system image in ROM, bytes of processor RAM installed, bytes of NVRAM installed, bytes of NVRAM in use, current configuration register setting, and the value of the configuration register at the next reload. The following installed card information is provided: type of card, serial number, hardware version, software version, and chassis slot number.
The chassis ID message can be seen with the show snmp command.
Examples
In the following example, the chassis serial number specified is 1234456:
snmp-server chassis-id 1234456Related Commands
snmp-server community
To set up the community access string to permit access to the Simple Network Management Protocol protocol, use the snmp-server community global configuration command. The no form of this command removes the specified community string.
snmp-server community string [view view-name] [ro | rw] [number]
no snmp-server community string
Syntax Description
Defaults
By default, an SNMP community string permits read-only access to all objects.
Note
If the snmp-server community command is not used during the SNMP configuration session, it will automatically be added to the configuration after the snmp host command is used. In this case, the default password (string) for the snmp-server community will be taken from the snmp host command.
Command Modes
Global configuration
Command History
Usage Guidelines
The no snmp-server command disables all versions of SNMP (SNMPv1, SNMPv2C, SNMPv3).
The first snmp-server command that you enter enables all versions of SNMP.
Examples
The following example assigns the string comaccess to SNMP allowing read-only access and specifies that IP access list 4 can use the community string:
snmp-server community comaccess ro 4The following example assigns the string mgr to SNMP allowing read-write access to the objects in the restricted view:
snmp-server community mgr view restricted rwThe following example removes the community comaccess:
no snmp-server community comaccessThe following example disables all versions of SNMP:
no snmp-serverRelated Commands
access-list
Configures the access list mechanism for filtering frames by protocol type or vendor code.
Creates or updates a view entry.
snmp-server contact
To set the system contact (sysContact) string, use the snmp-server contact global configuration command. Use the no form to remove the system contact information.
snmp-server contact text
no snmp-server contact
Syntax Description
Defaults
No system contact string is set.
Command Modes
Global configuration
Command History
Examples
The following is an example of a system contact string:
snmp-server contact Dial System Operator at beeper # 27345Related Commands
snmp-server context
This command is no longer valid. The functionality provided by this command has been removed from the Cisco IOS software.
snmp-server enable informs
This command has no functionality. To enable the sending of SNMP inform notifications, use the snmp-server enable traps [notification-type] command combined with the snmp-server host host-addr informs command.
snmp-server enable traps
To enable the router to send Simple Network Management Protocol traps or informs (SNMP notifications), use the snmp-server enable traps global configuration command. Use the no form of this command to disable SNMP notifications.
snmp-server enable traps [notification-type] [notification-option]
no snmp-server enable traps [notification-type] [notification-option]
Syntax Description
Defaults
This command is disabled by default. Most notification types are disabled. However, some notification types cannot be controlled with this command.
If you enter this command with no notification-type keywords, the default is to enable all notification types controlled by this command (EXCEPTION: ATM PVC notifications are not enabled unless the atm pvc keywords are used.)
Command Modes
Global configuration
Command History
Usage Guidelines
SNMP notifications can be sent as traps or inform requests. This command enables both traps and inform requests for the specified notification types. To specify whether the notifications should be sent as traps or informs, use the snmp-server host [traps | informs] command.
If you do not enter an snmp-server enable traps command, no notifications controlled by this command are sent. In order to configure the router to send these SNMP notifications, you must enter at least one snmp-server enable traps command. If you enter the command with no keywords, all notification types are enabled (with the exception of ATM PVC notifications). If you enter the command with a keyword, only the notification type related to that keyword is enabled. In order to enable multiple types of notifications, you must issue a separate snmp-server enable traps command for each notification type and notification option.
The snmp-server enable traps command is used in conjunction with the snmp-server host command. Use the snmp-server host command to specify which host or hosts receive SNMP notifications. In order to send notifications, you must configure at least one snmp-server host command.
For a host to receive a notification controlled by this command, both the snmp-server enable traps command and the snmp-server host command for that host must be enabled. If the notification type is not controlled by this command, just the appropriate snmp-server host command must be enabled.
The notification types used in this command all have an associated MIB object that allows them to be globally enabled or disabled. Not all of the notification types available in the snmp-server host command have notificationEnable MIB objects, so some of these cannot be controlled using the snmp-server enable command.
Examples
The following example enables the router to send all traps to the host specified by the name myhost.cisco.com, using the community string defined as public:
snmp-server enable trapssnmp-server host myhost.cisco.com publicThe following example enables the router to send Frame Relay and environmental monitor traps to the host myhost.cisco.com using the community string public:
snmp-server enable traps frame-relaysnmp-server enable traps envmon temperaturesnmp-server host myhost.cisco.com publicThe following example will not send traps to any host. The BGP traps are enabled for all hosts, but the only traps enabled to be sent to a host are ISDN traps (which are not enabled in this example).
snmp-server enable traps bgpsnmp-server host bob public isdnThe following example enables the router to send all inform requests to the host at the address myhost.cisco.com, using the community string defined as public:
snmp-server enable trapssnmp-server host myhost.cisco.com informs version 2c publicThe following example sends HSRP MIB traps to the host myhost.cisco.com using the community string public.
snmp-server enable hsrpsnmp-server host myhost.cisco.com traps version 2c public hsrpRelated Commands
snmp-server engineID
To configure a name for either the local or remote Simple Network Management Protocol engine on the router, use the snmp-server engineID global configuration command. To remove the configured engine ID, use the no form of this command .
snmp-server engineID [local engineid-string] | [remote ip-address udp-port port engineid-string]
no snmp-server engineID
Syntax Description
Defaults
An SNMP engine ID is generated automatically but is not displayed or stored in the running configuration. You can display the default or configured engine ID by using the show snmp engineID EXEC command.
Command Modes
Global configuration
Command History
Usage Guidelines
Note that you need not specify the entire 24-character engine ID if it contains trailing zeros. Specify only the portion of the Engine ID up until the point where only zeros remain in the value. To configure an engine ID of 123400000000000000000000, you can specify the value 1234, for example, snmp-server engineID local 1234.
Changing the value of snmpEngineID has important side-effects. A user's password (entered on the command line) is converted to an MD5 or SHA security digest. This digest is based on both the password and the local engine ID. The command line password is then destroyed, as required by RFC 2274. Because of this deletion, if the local value of engineID changes, the security digests of SNMPv3 users will be invalid, and the users will have to be reconfigured.
Similar restrictions require the reconfiguration of community strings when the engine ID changes. A remote engine ID is required when an SNMPv3 inform is configured. The remote engine ID is used to compute the security digest for authenticating and encrypting packets sent to a user on the remote host. Please refer to the examples in the Configuring Informs section in the snmp-server host command reference page.
Related Commands
snmp-server group
To configure a new Simple Network Management Protocol group, or a table that maps SNMP users to SNMP views, use the snmp-server group global configuration command. To remove a specified SNMP group, use the no form of this command.
snmp-server group [groupname {v1 | v2c | v3 {auth | noauth | priv}}] [read readview] [write writeview] [notify notifyview ] [access access-list]
no snmp-server group
Syntax Description
Defaults
Table 45 describes default values for the different views.
Command Modes
Global configuration
Command History
Usage Guidelines
When a community string is configured internally, two groups with the name public are autogenerated, one for the v1 security model and the other for the v2c security model. Similarly, deleting a community string will delete a v1 group with the name public and a v2c group with the name public.
Configuring Notify Views
Do not specify a notify view when configuring an SNMP group for the following reasons:
•
•
The notifyview option is available for two reasons:
•
•
Instead of specifying the notify view for a group as part of the snmp-server group command, use the following commands in global configuration mode:
Working with Passwords and Digests
No default values exist for authentication or privacy algorithms when you configure the command. Also, no default passwords exist. The minimum length for a password is one character, although Cisco recommends using eight characters for security. If you forget a password, you cannot recover it and will need to reconfigure the user. You can specify either a plain-text password or a localized MD5 digest.
The following example shows how to enter a plain-text password for the string arizona2 for user John in group Johngroup, type the following command line:
snmp-server user John Johngroup v3 auth md5 arizona2.When you enter a show running-config command, you will not see a line for this user. To see if this user has been added to the configuration, type the show snmp user command.
If you have the localized MD5 or SHA digest, you can specify that string instead of the plain-text password. The digest should be formatted as aa:bb:cc:dd where aa, bb, and cc are hex values. Also, the digest should be exactly 16 octets long.
The following example shows how to specify the command with a digest name of 00:11:22:33:44:55:66:77:88:99:AA:BB:CC:DD:EE:FF:
snmp-server user John Johngroup v3 encrypted auth md5 00:11:22:33:44:55:66:77:88:99:AA:BB:CC:DD:EE:FFRelated Commands
show snmp group
Displays the names of groups on the router and the security model, the status of the different views, and the storage type of each group.
snmp-server host
To specify the recipient of an Simple Network Management Protocol notification operation, use the snmp-server host global configuration command. To remove the specified host, use the no form of this command.
snmp-server host host-addr [traps | informs] [version {1 | 2c | 3 [auth | noauth | priv]}] community-string [udp-port port] [notification-type]
no snmp-server host host [traps | informs]
Syntax Description
Defaults
This command is disabled by default. No notifications are sent.
If you enter this command with no keywords, the default is to send all trap types to the host. No informs will be sent to this host.
If no version keyword is present, the default is version 1. The no snmp-server host command with no keywords will disable traps, but not informs, to the host. In order to disable informs, use the no snmp-server host informs command.
Note
Command Modes
Global configuration
Command History
10.0
This command was introduced.
12.0(3)T
The following keywords were added:
•
•
Usage Guidelines
SNMP notifications can be sent as traps or inform requests. Traps are unreliable because the receiver does not send acknowledgments when it receives traps. The sender cannot determine if the traps were received. However, an SNMP entity that receives an inform request acknowledges the message with an SNMP response PDU. If the sender never receives the response, the inform request can be sent again. Thus, informs are more likely to reach their intended destination.
However, informs consume more resources in the agent and in the network. Unlike a trap, which is discarded as soon as it is sent, an inform request must be held in memory until a response is received or the request times out. Also, traps are sent only once, while an inform may be retried several times. The retries increase traffic and contribute to a higher overhead on the network.
If you do not enter an snmp-server host command, no notifications are sent. In order to configure the router to send SNMP notifications, you must enter at least one snmp-server host command. If you enter the command with no keywords, all trap types are enabled for the host.
In order to enable multiple hosts, you must issue a separate snmp-server host command for each host. You can specify multiple notification types in the command for each host.
When multiple snmp-server host commands are given for the same host and kind of notification (trap or inform), each succeeding command overwrites the previous command. Only the last snmp-server host command will be in effect. For example, if you enter an snmp-server host inform command for a host and then enter another snmp-server host inform command for the same host, the second command will replace the first.
The snmp-server host command is used in conjunction with the snmp-server enable command. Use the snmp-server enable command to specify which SNMP notifications are sent globally. For a host to receive most notifications, at least one snmp-server enable command and the snmp-server host command for that host must be enabled.
However, some notification types cannot be controlled with the snmp-server enable command. For example, some notification types are always enabled. Other notification types are enabled by a different command. For example, the linkUpDown notifications are controlled by the snmp trap link-status command. These notification types do not require an snmp-server enable command.
A notification-type option's availability depends on the router type and Cisco IOS software features supported on the router. For example, the envmon notification-type is available only if the environmental monitor is part of the system.
Examples
If you want to configure a unique snmp community string for traps, but you want to prevent snmp polling access with this string, the configuration should include an access-list. In the following example, the community string is named "comaccess" and the access list is numbered 10:
snmp-server community comaccess ro 10snmp-server host 172.20.2.160 comaccessaccess-list 10 deny anyThe following example sends the SNMP traps to the host specified by the name myhost.cisco.com. The community string is defined as comaccess.
snmp-server enable trapssnmp-server host myhost.cisco.com comaccess snmpThe following example sends the SNMP and Cisco environmental monitor enterprise-specific traps to address 172.30.2.160:
snmp-server enable trapssnmp-server host 172.30.2.160 public snmp envmonThe following example enables the router to send all traps to the host myhost.cisco.com using the community string public:
snmp-server enable trapssnmp-server host myhost.cisco.com publicThe following example will not send traps to any host. The BGP traps are enabled for all hosts, but only the ISDN traps are enabled to be sent to a host.
snmp-server enable traps bgpsnmp-server host bob public isdnThe following example enables the router to send all inform requests to the host myhost.cisco.com using the community string public:
snmp-server enable trapssnmp-server host myhost.cisco.com informs version 2c publicThe following example sends HSRP MIB traps to the host specified by the name myhost.cisco.com. The community string is defined as public.
snmp-server enable hsrpsnmp-server host myhost.cisco.com traps version 2c public hsrpRelated Commands
snmp-server informs
To specify inform request options, use the snmp-server informs global configuration command. The no form of this command returns the settings to the defaults.
snmp-server informs [retries retries] [timeout seconds] [pending pending]
no snmp-server informs [retries retries] [timeout seconds] [pending pending]
Syntax Description
Defaults
Inform requests are resent three times. Informs are resent after 30 seconds if no response is received. The maximum number of informs waiting for acknowledgments at any one time is 25.
Command Modes
Global configuration
Command History
Examples
The following example increases the pending queue size if you are seeing a large number of inform drops:
snmp-server informs pending 50The following example increases the default timeout if you are sending informs over slow network links. Because informs will be sitting in the queue for a longer period of time, you may also need to increase the pending queue size.
snmp-server informs timeout 60 pending 40The following example decreases the default timeout if you are sending informs over very fast links:
snmp-server informs timeout 5The following example increases the retry count if you are sending informs over unreliable links. Because informs will be sitting in the queue for a longer period of time, you may need to increase the pending queue size.
snmp-server informs retries 10 pending 45Related Commands
snmp-server location
To set the system location string, use the snmp-server location global configuration command. Use the no form of this command to remove the location string.
snmp-server location text
no snmp-server location
Syntax Description
Defaults
No system location string is set.
Command Modes
Global configuration
Command History
Examples
The following example illustrates a system location string:
snmp-server location Building 3/Room 214Related Commands
snmp-server manager
To start the Simple Network Management Protocol manager process, use the snmp-server manager global configuration command. The no form of this command stops the SNMP manager process.
snmp-server manager
no snmp-server manager
Syntax Description
This command has no arguments or keywords.
Defaults
Disabled
Command Modes
Global configuration
Command History
Usage Guidelines
The SNMP manager process sends SNMP requests to agents and receives SNMP responses and notifications from agents. When the SNMP manager process is enabled, the router can query other SNMP agents and process incoming SNMP traps.
Most network security policies assume that routers will be accepting SNMP requests, sending SNMP responses, and sending SNMP notifications. With the SNMP manager functionality enabled, the router may also be sending SNMP requests, receiving SNMP responses, and receiving SNMP notifications. The security policy implementation may need to be updated prior to enabling this functionality.
SNMP requests are typically sent to UDP port 161. SNMP responses are typically sent from UDP port 161. SNMP notifications are typically sent to UDP port 162.
Examples
The following example enables the SNMP manager process:
snmp-server managerRelated Commands
snmp-server manager session-timeout
To set the amount of time before a nonactive session is destroyed, use the snmp-server manager session-timeout global configuration command. The no form of this command returns the value to its default.
snmp-server manager session-timeout seconds
no snmp-server manager session-timeout
Syntax Description
Defaults
Idle sessions time out after 600 seconds (10 minutes).
Command Modes
Global configuration
Command History
Usage Guidelines
Sessions are created when the SNMP manager in the router sends SNMP requests, such as inform requests, to a host or receives SNMP notifications from a host. One session is created for each destination host. If there is no further communication between the router and host within the session timeout period, the session will be deleted.
The router tracks statistics, such as the average round-trip time required to reach the host, for each session. Using the statistics for a session, the SNMP manager in the router can set reasonable timeout periods for future requests, such as informs, for that host. If the session is deleted, all statistics are lost. If another session with the same host is later created, the request timeout value for replies will return to the default value.
However, sessions consume memory. A reasonable session timeout value should be large enough such that regularly used sessions are not prematurely deleted, yet small enough such that irregularly used, or one-shot sessions, are purged expeditiously.
Examples
The following example sets the session timeout to a larger value than the default:
snmp-server managersnmp-server manager session-timeout 1000Related Commands
Displays the current set of pending SNMP requests.
Displays the current SNMP sessions.
Starts the SNMP manager process.
snmp-server packetsize
To establish control over the largest Simple Network Management Protocol packet size permitted when the SNMP server is receiving a request or generating a reply, use the snmp-server packetsize global configuration command. Use the no form of this command to restore the default value.
snmp-server packetsize byte-count
no snmp-server packetsize
Syntax Description
Defaults
1500 bytes
Command Modes
Global configuration
Command History
Examples
The following example establishes a packet filtering of a maximum size of 1024 bytes:
snmp-server packetsize 1024Related Commands
snmp-server queue-length
To establish the message queue length for each trap host, use the snmp-server queue-length global configuration command.
snmp-server queue-length length
Syntax Description
length
Integer that specifies the number of trap events that can be held before the queue must be emptied.
Defaults
10 events
Command Modes
Global configuration
Command History
Usage Guidelines
This command defines the length of the message queue for each trap host. Once a trap message is successfully transmitted, software will continue to empty the queue, but never faster than at a rate of four trap messages per second.
Examples
The following example establishes a message queue that traps four events before it must be emptied:
snmp-server queue-length 4Related Commands
Establishes control over the largest SNMP packet size permitted when the SNMP server is receiving a request or generating a reply.
snmp-server system-shutdown
To use the Simple Network Management Protocol message reload feature, the router configuration must include the snmp-server system-shutdown global configuration command. The no form of this command prevents an SNMP system-shutdown request (from an SNMP manager) from resetting the Cisco agent.
snmp-server system-shutdown
no snmp-server system-shutdown
Syntax Description
This command has no arguments or keywords.
Defaults
This command is not included in the configuration file.
Command Modes
Global configuration
Command History
Examples
The following example enables the SNMP message reload feature:
snmp-server system-shutdownsnmp-server tftp-server-list
To limit the TFTP servers used via Simple Network Management Protocol-controlled TFTP operations (saving and loading configuration files) to the servers specified in an access list, use the snmp-server tftp-server-list global configuration command. To disable this feature, use the no form of this command.
snmp-server tftp-server-list number
no snmp-server tftp-server-list
Syntax Description
Defaults
Disabled
Command Modes
Global configuration
Command History
Examples
The following example limits the TFTP servers that can be used for configuration file copies via SNMP to the servers in access list 44:
snmp-server tftp-server-list 44snmp-server trap-authentication
The snmp-server enable traps snmp authentication command replaces this command. See the snmp-server host command in this chapter for more information.
snmp-server trap-source
To specify the interface (and hence the corresponding IP address) that an Simple Network Management Protocol trap should originate from, use the snmp-server trap-source global configuration command. Use the no form of the command to remove the source designation.
snmp-server trap-source interface
no snmp-server trap-source
Syntax Description
interface
Interface from which the SNMP trap originates. The argument includes the interface type and number in platform-specific syntax.
Defaults
No interface is specified.
Command Modes
Global configuration
Command History
Usage Guidelines
When an SNMP trap is sent from a Cisco SNMP server, it has a trap address of whatever interface it happened to go out of at that time. Use this command if you want to use the trap address to trace particular needs.
Examples
The following example specifies that the IP address for interface Ethernet 0 is the source for all traps:
snmp-server trap-source ethernet 0The following example specifies that the IP address for interface Ethernet 2/1 on a Cisco 7000 is the source for all traps:
snmp-server trap-source ethernet 2/1Related Commands
Enables a router to send SNMP traps and informs.
Specifies the recipient of an SNMP notification operation.
snmp-server trap-timeout
To define how often to try resending trap messages on the retransmission queue, use the snmp-server trap-timeout global configuration command.
snmp-server trap-timeout seconds
Syntax Description
Defaults
30 seconds
Command Modes
Global configuration
Command History
Usage Guidelines
Before the Cisco IOS software tries to send a trap, it looks for a route to the destination address. If there is no known route, the trap is saved in a retransmission queue. The server trap-timeout command determines the number of seconds between retransmission attempts.
Examples
The following example sets an interval of 20 seconds to try resending trap messages on the retransmission queue:
snmp-server trap-timeout 20Related Commands
Specifies the recipient of an SNMP notification operation.
Establishes the message queue length for each trap host.
snmp-server user
To configure a new user to an Simple Network Management Protocol group, use the snmp-server user global configuration command. To remove a user from an SNMP group, use the no form of the command.
snmp-server user username [groupname remote ip-address [udp-port port] {v1 | v2c | v3} [encrypted] [auth {md5 | sha} auth-password [priv des56 priv password]] [access access-list]
no snmp-server user
Syntax Description
Defaults
Table 46 describes default values for the encrypted option, passwords and access lists.
Command Modes
Global configuration
Command History
Usage Guidelines
To configure a remote user, specify the IP address or port number for the remote SNMP agent of the device where the user resides. Also, before you configure remote users for a particular agent, configure the SNMP engine ID, using the command snmp-server engineID with the remote option. The remote agent's SNMP engine ID is needed when computing the authentication/privacy digests from the password. If the remote engine ID is not configured first, the configuration command will fail.
SNMP passwords are localized using the SNMP engine ID of the authoritative SNMP engine. For informs, the authoritative SNMP agent is the remote agent. You need to configure the remote agent's SNMP engine ID in the SNMP database before you can send proxy requests or informs to it.
Related Commands
show snmp user
Displays information on each SNMP username in the group username table.
snmp-server view
To create or update a view entry, use the snmp-server view global configuration command. To remove the specified Simple Network Management Protocol server view entry, use the no form of this command.
snmp-server view view-name oid-tree {included | excluded}
no snmp-server view view-name
Syntax Description
Defaults
No view entry exists.
Command Modes
Global configuration
Command History
Usage Guidelines
Other SNMP commands require a view as an argument. You use this command to create a view to be used as arguments for other commands that create records including a view.
Two standard predefined views can be used when a view is required, instead of defining a view. One is everything, which indicates that the user can see all objects. The other is restricted, which indicates that the user can see three groups: system, snmpStats, and snmpParties. The predefined views are described in RFC 1447.
The first snmp-server command that you enter enables both versions of SNMP.
Examples
The following example creates a view that includes all objects in the MIB-II subtree:
snmp-server view mib2 mib-2 includedThe following example creates a view that includes all objects in the MIB-II system group and all objects in the Cisco enterprise MIB:
snmp-server view phred system includedsnmp-server view phred cisco includedThe following example creates a view that includes all objects in the MIB-II system group except for sysServices (System 7) and all objects for interface 1 in the MIB-II interfaces group:
snmp-server view agon system includedsnmp-server view agon system.7 excludedsnmp-server view agon ifEntry.*.1 includedRelated Commands
snmp trap link-status
To enable Simple Network Management Protocol link trap generation, use the snmp trap link-status interface configuration command. To disable SNMP link traps, use the no form of this command.
snmp trap link-status
no snmp trap link-status
Syntax Description
This command has no arguments or keywords.
Defaults
SNMP link traps are sent when an interface goes up or down.
Command Modes
Interface configuration
Command History
Usage Guidelines
By default, SNMP link traps are sent when an interface goes up or down. For interfaces expected to go up and down during normal usage, such as ISDN interfaces, the output generated by these traps may not be useful. The no form of this command disables these traps.
Examples
The following example disables the sending of SNMP link traps related to the ISDN BRI 0 interface:
interface bri 0no snmp trap link-status
