SNMP polls bring down routers

[mwilmes]

Hello,
I'm new to NetXMS, but not to monitoring softwares.  I was performing a trial run to generate a network map through our two core routers using SNMP v3.  I entered the credentials and was able to pull data from our extended infrastructure, but after about two hours we would begin seeing rolling and intermittent network outages.  These outages stopped when I shut down the NetXMS server, and resurfaced when I brought it back online.  Doing some research into the outages, the cause was determined to be CPU overload on the core routers.

Is anyone aware of any feature or setting that would cause this if configured incorrectly?  I'm running the NetXMS server on a Windows VM, and the VM was operating within normally expected parameters.  I did not change any of the default settings.  The SNMP credentials have read-only access to the entire SNMP tree on the routers.  The routers are Enterasys S4 devices.

Thank you,
Mike

[Jmp_3f8h]

I had similar problem with a very old DLINK switch:

https://www.netxms.org/forum/configuration/snmp-monitoring-problem/

Sounds like a similar scenario.

Regards,
Marco

[victor]

Hi,

for core routers you may try to disable routing table poll - if routing tables are large reading it over SNMP may cause significant load. We also encounter SNMPv3 specific issues on some devices - switching to SNMPv2 solves them.

Best regards,
Victor