Highlighted
SteveLee2
6 Indium

Discovery errors: Agent loops in response to GET_NEXT

We are having a discovery problem with Brocade/Foundry switches. On certain model switches, we get a discovery error of “SWFE-E-ELOOP-Agent loops in response to GET_NEXT: Agent: 10.2.6.10, First OID: .1.3.6.1.2.1.17.4.3.1.2.188.48.91.195.241.165“, with a different OID every time.

An snmpwalk of the switch fails with the following, also with different OIDs:

Error: OID not increasing:

>>>>>> SNMPv2-SMI::mib-2.17.4.3.1.1.212.190.217.159.4.181

>>>>>>> = SNMPv2-SMI::mib-2.17.4.3.1.1.0.24.139.90.156.245

The vendor is recommending that we use the “-Cc” flag. They reference the man page for snmpwalk:

“Some agents (LaserJets are an example) return OIDs out of order, but

can complete the walk anyway. Other agents return OIDs that are out of

order and can cause snmpwalk to loop indefinitely. By default, snmpwalk

tries to detect this behavior and warns you when it hits an agent

acting illegally. Use -Cc to turn off this behavior as -Cc Do not check

whether the returned OIDs are increasing.”

Is there a way to do this in ItOps IP 8.1.2?

Btw, I have tried SNMP v1 and v2c. Both have the same results.

Thanks.

Steve

0 Kudos
4 Replies

Re: Discovery errors: Agent loops in response to GET_NEXT

Hi Steve,

In IP 7.0.4 & 8.1.2 there were changes to fix some issues with a looping snmp agent. There is a --loop option in snmpwalk that can be used to try and get around this issue. However, if you are running 8.1.2 and still have issues with discovery, it may be worth logging a ticket and including the log file (when run in debug mode) to the ticket to see if an Enhancement request is needed or the problem is with the vendor MIB. Many thanks Mark

0 Kudos

Re: Discovery errors: Agent loops in response to GET_NEXT

One other thing I forgot to mention, if you are running McAfee or similar, disable this for a short while and see if that makes a difference.

0 Kudos
SteveLee2
6 Indium

Re: Discovery errors: Agent loops in response to GET_NEXT

The question really pertains to discoveries in Smarts. Is there a way to do this in discovery.conf or with sm_tpmgr?

0 Kudos
8 Krypton

Re: Discovery errors: Agent loops in response to GET_NEXT

The short answer is no.  For the sm_snmpwalk utility there is some logic to try and skip ahead to the next branch of the SNMP MIB, but during discovery, we are attempting to probe specific leaf entries - not just get the full tree. 

I would suggest that your course of action here is to talk to support to change the certification for the device which will avoid the problematic spots in the MIB. 

0 Kudos