How to monitor VLAN trffic

[tvm_parthiban83]

I want to Monitor Vlan traffic

some of our equipment is not supported SNMP.

so all our customer gateway is defined in NoC L3 swith

as a differnt VLAN

when ever we try to take MRTG from L3 it shows vlan traffic is 100bits/sec but this customer is geetiing 2 MB/sec

how can we monitor any idea or help

[Marvin Rhoads]

Are you sure you're querying the correct MIB ifindex? Use "sh snmp mib ifmib ifindex" from the CLI to verify the ifindex number you want to query.

Hope this helps. Please rate helpful posts.

[b.henshaw]

As far as I'm aware (at least on the layer 3 switches I've dealt with) you can't get per-VLAN throughput statistics by monitoring SVIs/VLAN interfaces.

If you want per-VLAN stats (assuming you're trunking multiple VLANs over a single interface and want the stats for one VLAN) you may be able to poll the CISCO-CLASS-BASED-QOS-MIB if you're using policies on your physical interfaces.

I haven't found another way to obtain per-VLAN stats - I'd be happy to be corrected.

Of course it may be viable in your situation (depending on the connectivity) to simply monitor the physical ports to which customer routers are attached. (or maybe not, hence your VLAN question)

[tvm_parthiban83]

I dont find any OID related to interface in/out packets and bits in that MIB.

any other ways to proceed further

pls help out.

[damirs]

On some Cisco L3 switches, you cannot measure traffic via SNMP on VLAN interface since it shows unreal speed. There is no workaround. If you cannot measure port connected to customer it will be a problem. If your L3 switch supports NETFLOW there is a way but it may be costly to implement. From NETFLOW database you can do calculations of customers speed.

In any case, if you chose this there are lot more different things that you can analyze with NETFLOW database.

Regards,