• September 21, 2020, 09:30:10 PM
Welcome, Guest. Please login or register. Registration is free.
Did you miss your activation email?

Author Topic: ERS 4800 SNMP monitoring creates high CPU  (Read 2408 times)

0 Members and 1 Guest are viewing this topic.

Offline jnfohr

  • Rookie
  • **
  • Posts: 4
ERS 4800 SNMP monitoring creates high CPU
« on: July 21, 2015, 10:26:52 AM »
Hi

I have been deploying a few ERS 4850 stacks for my company the past weeks an i realized that when i try to fetch snmp information with my monitoring tools, the base CPU reaches 85 to 95% for a long time, which results in 90% level of cpu utilization for the base since bootup, and it is therefore impossible to monitor the switch.

I'm normally using the following config for SNMP on my ERS4500 or ERS5000 which perform just fine:


snmp-server view all +1.3
snmp-server user abc md5 "***" des "***" read-view all write-view all
snmp-server enable
no snmp-server community rw
no snmp-server community ro

and i also tried disabling the snmp v3 and using snmp v2c only with the same issue.

My monitoring tools are Check_MK which fetches interface counters info and Netdisco which does macsuck and topology discovery.

Has anyone else encountered this issue, does anyone has an idea what's wrong there?

Thanks

Jean-Noel


Offline Telair

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 965
Re: ERS 4800 SNMP monitoring creates high CPU
« Reply #1 on: July 21, 2015, 02:54:04 PM »
What software level are you running.  Also, how often are you polling the switch?

Offline jnfohr

  • Rookie
  • **
  • Posts: 4
Re: ERS 4800 SNMP monitoring creates high CPU
« Reply #2 on: July 21, 2015, 07:09:03 PM »
I upgraded to the latest version last week hoping it would solve my CPU issues, that was before i found out SNMP polls were causing the high levels, so i'm running 5.8.1.301 now.

The interface polling is at the default one which is 1 minutes i think.

Offline Dominik

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 1564
    • Networkautobahn
Re: ERS 4800 SNMP monitoring creates high CPU
« Reply #3 on: July 22, 2015, 03:39:56 AM »
I also had some problems with high CPu utilization on ERS4800 stacks.

Do you run L3, VLACP or SPB on your ERS4k ?
I also use Check_Mk there it looks like that the 10Sec and 1 Min graph show the doubled value of the correct CPU utilization, you can see that if you compare it to the 10min graph.

I also have the feeling that 1min polling was to cpu intense for the ERS4k , so I went down to polling every 5min on all ERS4k stacks. Single units looks more relaxed regarding to cpu utilization.

Did the update to SW 5.8.1.301 change anything regarding to the CPU utilization ?

Cheers
Itīs always the networks fault!
networkautobahn.com

Offline jnfohr

  • Rookie
  • **
  • Posts: 4
Re: ERS 4800 SNMP monitoring creates high CPU
« Reply #4 on: July 22, 2015, 01:38:16 PM »
Hi Dominik

I do run SPB on the 4850, but not VLACP nor L3. And no there's been no change after upgrading.
Actualy all the values, from 10 sec to bootup were at 90% of CPU for the base unit. That's a bit surprising that switches supposed to be more powerful than the ERS4500 cannot handle the same kind of SNMP requests.
I do have  a 2 units stack that performs much better than my other 8 units ones, so it's certainly related to the nomber of interfaces to poll. I've increased the interval, 5 minutes seem to be  enough for a poll, though it still keeps the CPU busy .