[j-nsp] Monitoring interface counters on J/SRX

[Clarke Morledge]

Dale,

I have run into the same issues you have with the interface counters. 
The physical interface counters give you the most amount of detail, not 
only with respect to errors, discards, etc,, but with multicast/broadcast 
vs. unicast, too.  The logical interface counters only help with basic 
packet and octet counters.  And by "logical" interface this also applies 
to things like Integrated Routing and Bridging (IRB) interfaces.

As you pointed out, you can measure bandwidth just fine for logical 
interfaces, but pretty much everything else just reads as zero in the 
MIBs.  This applies to the standard IF-MIB as well as the proprietary 
jnxMib.

You can use filters for counting purposes on logical interfaces, and that 
helps make up for what isn't available by default, but from what I have 
seen filters do not dig down into the physical error realm.

Hope that helps somewhat.

Clarke Morledge
College of William and Mary
Information Technology - Network Engineering
Jones Hall (Room 18)
Williamsburg VA 23187


On Sat, 12 Feb 2011, Dale said,

> Message: 3
> Date: Sat, 12 Feb 2011 20:10:02 +1100
> From: Dale Shaw <dale.shaw+j-nsp at gmail.com>
> To: juniper-nsp <juniper-nsp at puck.nether.net>
> Subject: [j-nsp] Monitoring interface counters on J/SRX
> Message-ID:
> 	<AANLkTinQS23_oq58gnpCuvrS+y2KPpjzyoEn-HDCpEAe at mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Hi,
>
> [ disclaimer: I don't claim to be a network management expert but I
> can spell SMTP* ]
>
> In our network, we capture, graph and report on the usual set of
> interface counters - errors and discards in/out, octets in/out,
> packets in/out and so on. Most of the in-house skills are with Cisco
> products but we're getting a lot better with J.
>
> I'm trying to come to terms with the difference between the physical
> (ifd) counters and the logical (ifl) counters for both 'family inet'
> and 'family ethernet-switching' interfaces.
>
> I'm facing a few dilemmas;
> 1) on Ethernet interfaces shaped to sub line rate, only logical units
> report the 'correct' bandwidth so in order for our graphs to scale
> correctly we either have to perform interface utilisation reporting
> against the logical unit(s), or manually configure our NMS with the
> shaped/provisioned bandwidth value. In most cases we're only using one
> logical unit (unit 0).
> 2) I noticed recently that our NMS is collecting error/discard
> counters from logical interfaces, and these appear to be always zero.
> A few CLI checks around the network seem to prove the theory -
> error/discard counters must be collected from the physical interface.
>
> What's the "right" thing to do here? If there is no right/wrong, what
> works for you?
>
> Anyway, I suppose what I'm really looking for is some generic advice
> on how to monitor interfaces in Juniper routers and switches -- are
> the standard MIBs OK? I just noticed there appear to be interface
> counters in jnxMibs. Do you grab interface error/discard counters from
> the physical only? Is there a way to populate logical interface
> error/discard counters with the underlying physical interface's
> counters? (it seems the logical interface does not track
> errors/discards, which I guess makes sense).
>
> More than happy to be pointed at good documentation.
>
> Cheers,
> Dale
>
> * That was a hilarious joke.