SNMP - monitoring large number of devices

Dan White dwhite at olp.net
Tue Sep 29 20:37:51 UTC 2015


On 09/29/15 22:20 +0200, Pavel Dimow wrote:
>recently I have been tasked with a NMS project. The idea is to pool about
>20 OID's from 50k cable modems in less then 5 minutes (yes, I know it's a
>one million OID's). Before you say check out some very professional and
>expensive solutions I would like to know are there any alternatives like
>open source "snmp framework"? To be more descriptive many of you knows how
>big is the mess with snmp on cable modem. You always first perform snmp
>walk in order to discover interfaces and then read the values for those
>interfaces. As cable modem can bundle more DS channels, one time you can
>have one and other time you can have N+1 DS channels = interfaces. All in
>all I don't believe that there is something perfect out there when it comes
>to tracking huge number of cable modems so I would like to know is there
>any "snmp framework" that can be exteded and how did you (or would you)
>solve this problem.

I've done about ~60,000 OID queries (over a few dozen devices) per 5
minutes using OpenNMS, which is Java based. At the scale you're looking at,
disk I/O would be a major performance issue (if using rrdtool). Google for
'Tuning RRD' for some tips that can make a significant difference.

-- 
Dan White



More information about the NANOG mailing list