[Lustre-devel] Feature request: expand SNMP scope

[Kilian CAVALOTTI]

Bonjour Patrice,

On Wednesday 12 March 2008 07:00:05 am patrice.lucas at cea.fr wrote:
> This method is not 
> integrated to the inner Lustre code. If people change /proc entries,
> the snmp agent code must clearly be rewrite. I agree with you when
> you emphasize the need to link the snmp code to the rest of the
> Lustre development.

Yes, that's what Brian first pointed out, and I think that's really the 
cornerstone here. Manually editing the SNMP code and the corresponding 
MIB files each time a new metric is added, removed or renamed, will 
rapidly get to be a nightmare.

>  From a more integrated point of view, do you think it could be a
> good idea to benefit from Lustre itself to deliver monitoring data ?
> Lustre is a parallel filesystem. Data delivered by Lustre can be
> accessed by remote client. Instead of using "/proc", can Lustre
> benefits from its capability of distributed filesystem to deliver
> monitoring data ? By doing that, we could lose the advantage of snmp
> to interface with many available common snmp network monitoring
> tools.

Well, yes, actually, that sounds like a very reasonnable approach too. 
The main advantages for SNMP, from my standpoint are the following:

1. It's a network protocol, so the monitored system doesn't have to be 
   the same as the monitoring one. This allows remote collection of 
   metrics, aggregation, and central administration.

2. It's an industry standard (even if vendors sometimes tend to have a 
   proprietary interpretation of what is a 'standard'), so it can be 
   used across a large variety of monitoring systems. Interoperability 
   is always a good thing

But only point 1. is really required to allow easier Lustre monitoring. 
If all the lnet/client/oss/mds data could be accessed from clients, 
that would be enough. One specific client (potentially patchless) could 
be dedicated for monitoring with almost the same advantage as a SNMP 
host.

That looks like the OFED approach: SNMP is not a priority for 
OpenFabrics, since the IB counters from all over the fabric can be 
gathered with a single perfquery, from a simple IB node.

And this may also be easier to implement than mapping SNMP exports to 
the Lustre stats files.

Cheers,
-- 
Kilian