18.3.2 Checking communication with SNMP managers

When you manage networks using the SNMP protocol by configuring the SNMP agent functionality on the Switch, check the following:

MIBs on the Switch can be retrieved from an SNMP manager on a network.
SNMP notification must be sent from the Switch to SNMP manager on the network. In addition, if the Switch is an inform, it must be able to receive a reply.

You can use the show snmp command to check the status of communication with an SNMP manager.

Figure 18-32: Result of executing show snmp command
> show snmp Date 20XX/12/27 15:06:08 UTC Contact: Suzuki@example.com Location: ServerRoom SNMP packets input : 137 (get:417 set:2) Get-request PDUs : 18 Get-next PDUs : 104 Get-bulk PDUs : 0 Set-request PDUs : 6 Response PDUs : 3 (with error 0) Error PDUs : 7 Bad SNMP version errors: 1 Unknown community name : 5 Illegal operation : 1 Encoding errors : 0 SNMP packets output : 185 Trap PDUs : 4 Inform-request PDUs : 53 Response PDUs : 128 (with error 4) No errors : 124 Too big errors : 0 No such name errors : 3 Bad values errors : 1 General errors : 0 Timeouts : 49 Drops : 0 [TRAP] Host: 192.168.0.1, sent:1 Host: 192.168.0.2, sent:3 [INFORM] Timeout(sec) : 10 Retry : 5 Pending informs : 1/25 (current/max) Host: 192.168.0.3 sent :8 retries:26 response:2 pending:1 failed:5 dropped:0 Host: 192.168.0.4 sent :3 retries:15 response:0 pending:0 failed:3 dropped:0 Host: 2001:db8::10 sent :1 retries:0 response:1 pending:0 failed:0 dropped:0

Figure 18-32: Result of executing show snmp command

> show snmp 
Date 20XX/12/27 15:06:08 UTC
Contact: Suzuki@example.com
Location: ServerRoom
SNMP packets input  : 137    (get:417 set:2)
    Get-request PDUs    : 18
    Get-next PDUs       : 104
    Get-bulk PDUs       : 0
    Set-request PDUs    : 6
    Response PDUs       : 3    (with error 0)
    Error PDUs          : 7
        Bad SNMP version errors: 1
        Unknown community name : 5
        Illegal operation      : 1
        Encoding errors        : 0
 
SNMP packets output : 185
    Trap PDUs           : 4
    Inform-request PDUs : 53
    Response PDUs       : 128    (with error 4)
        No errors              : 124
        Too big errors         : 0
        No such name errors    : 3
        Bad values errors      : 1
        General errors         : 0
    Timeouts            : 49
    Drops               : 0
 
[TRAP]
    Host: 192.168.0.1, sent:1
    Host: 192.168.0.2, sent:3
 
[INFORM]
    Timeout(sec)       : 10
    Retry              : 5
    Pending informs    : 1/25 (current/max)
    Host: 192.168.0.3
        sent    :8          retries:26
        response:2          pending:1          failed:5          dropped:0
    Host: 192.168.0.4
        sent    :3          retries:15
        response:0          pending:0          failed:3          dropped:0
    Host: 2001:db8::10
        sent    :1          retries:0
        response:1          pending:0          failed:0          dropped:0

If MIBs cannot be obtained from the SNMP manager, make sure that the value for Error PDUs under SNMP packets input has not increased and PDUs have been successfully received. If the value for Error PDUs has increased, check the configuration settings. If PDUs have failed to be received, make sure that the network settings are correct and no error occurred on the route to the SNMP manager.

If you cannot receive SNMP notifications in SNMP Manager, check that IP addressof SNMP Manager is set as "Host" in the "[TRAP]" and "[INFORM]" items. If the IP address of the SNMP manager has not been set, execute the snmp-server host configuration command to set information about the SNMP manager.

If you cannot resolve the problem with these methods, refer to the Troubleshooting Guide. For details about MIB and SNMP notifications that can be obtained from the Switch, see MIB Reference.