Re: [Testbed-admins] need advice regarding "SNMP GET failed"

[Keith Sklower <sklower@vangogh.CS.Berkeley.EDU>]

The evidence you supplied makes it seem highly likely that whoever
upgraded the switch changed the read-write community name:

Either that or there is misconfiguartion so that the by the time
snmpit talks to the switch, it is supplying the wrong community
name.  Do you see the errors below on the experiment switch 
C388 Unknown community name" ?

When we do a "show running config" on our cisco switch it doesn't
tell us what the snmp community strings are, but if we save the
config via tftp to our server it is in the saved config file.

The community string supplied should be that in the snmp_community
strings column in the switch_stack_types table.  It should be 
a read-write string.

They could, in principal be different for the Experiment and Control
stack-id's.

Good Luck,

Keith Sklower


    From: "Cheng Cui" <ccui1@tigers.lsu.edu>
    Date: Sun, 12 Apr 2009 11:02:01 -0500

    Thanks Kevin. 

    It seems the our experiment switch does not work fine with snmp. I tried the
    snmpget on both Control and Experiment switch. Only control switch can give
    me some feedback of system information. The experiment switch is always time
[snip]
    Furthermore, I found the experiment switch was upgraded by someone
    because it's IOS was not the same as the control switch. Such as:

    Experiment switch:
    Cisco IOS Software, C3560 Software (C3560-ADVIPSERVICESK9-M), Version
    12.2(37)SE1

    Control switch:
    Cisco IOS Software, C3560 Software (C3560-IPSERVICES-M), Version
    12.2(25)SEB4


    However, I checked the snmp configuration on both switches. Both of them
    looks fine. Some information is as follows:

    Experiment switch:
    cisco2#show snmp 
    Chassis: FOC1023Y0MP
    643 SNMP packets input
	0 Bad SNMP version errors
	388 Unknown community name
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[snip]
	0 Illegal operation for community name supplied
    SNMP global trap: disabled
     
    SNMP logging: disabled
    SNMP agent enabled
    ***********************************
    Control switch:
    cisco1#show snmp 
    Chassis: FOC1023Y0N1
    2 SNMP packets input
	0 Bad SNMP version errors
	0 Unknown community name
[snip]


Here's some output from our setup.

You'll notice that if you run snmpit -v 1 <other args>
it will *tell* you what community string it is trying.

%mysql tbdb
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 242546 to server version: 5.0.20-log

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> select * from switch_stack_types;
+------------+------------+------------------+---------------+----------------+----------+----------+----------+
| stack_id   | stack_type | supports_private | single_domain | snmp_community | min_vlan | max_vlan | leader   |
+------------+------------+------------------+---------------+----------------+----------+----------+----------+
| Experiment | generic    | 0                | 0             | private        | 1040     | 1999     | Bnortele |
| Control    | generic    | 0                | 0             | private        | 1040     | 1999     | Bnortelc |
+------------+------------+------------------+---------------+----------------+----------+----------+----------+
2 rows in set (0.01 sec)

mysql> select * from switch_stacks;
+-----------+------------+------------+
| node_id   | stack_id   | is_primary |
+-----------+------------+------------+
[snip]
| Bnortelc  | Control    | 1          |
| Bnortele  | Experiment | 1          |
[snip]
mysql> 
Suspended
%
%snmpit -i Bnortelc -l -w -v 1
Debug level is 1
FILLING %Interfaces
FILLING %Ports
Operation is listvlans
Device names: Bnortelc
Ports: 
Stack Control has type generic
Making device object for Bnortelc
snapping Bnortelc 
Options for Bnortelc:
max_vlan = 1999
leader = Bnortelc
supports_private = 0
stack_type = generic
min_vlan = 1040
snmp_community = private
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
stack_id = Control
type = nortel5510
single_domain = 0
snmpit_nortel initializing B