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New Member

VoIP Monitoring the VLAN

Can someone tell me if VoIP monitoring is supported for then entire VLAN even if is spans 2 switches in the same closet (i.e. connected via trunked gigabit).

The scenario is thus: CRS Dual NIC (one used for sniffing).

Inbound PRI comes into Router A. Router A plugged into Switch A

Outbound PRI goes out Router B. Rouber B plugged into Switch B

CRS Pluggined into Switch A (along with it's sniffing NIC)

Pub Plugged into Switch A

Sub Plugged into Switch B

Switch A plugged into Switch B via trunked gigbit.

Agents split amont the switches

Switches are CAT 4006 Sup III running Cisco IOS (not CAT OS). This means RSPAN is not supported.

All voice devices are using VLAN 600, including Routers, CRS, phones, etc. Monitoring is configured thus.

mon sess 1 dest int x/yy (the sniff port)

mon sess 1 source vlan600 rx

I can successfully record/monitor all calls from the PSTN (to agents in both switches

I can successfully record/monitor all calls between agents between switch A and B

I can successfully record/monitor all outbound calls from agents plugged into switch A

I can only monitor/record the Agent side of the conversation with outbound calls placed from agents in switch B.

Moving the Router B to switch A is not an option for this Customer at this time due to Customer requirements.

Any thoughts?

Thanks in Advance


Re: VoIP Monitoring the VLAN

There are many tools used for VoIP Monitoring like:

1. Quality of Service Device Manager (QDM)

2. Network Monitoring Using Cisco Service Assurance Agent (CSSA)

3. CiscoWorks Voice Health Monitor

4. Data Sheet Network Analysis Module (NAM) for Cisco Catalyst 6500 and 6000 Series

5. Cisco Gateway Management Agent (CGMA)

More info on this can be found on :

CiscoView can also be used to monitor the VLANs

New Member

Re: VoIP Monitoring the VLAN


However, this thread is in regards to the VoIP Monitor Server for IPCC that allows one to Record and Listen to voice calls using the VoIP Monitor.


Re: VoIP Monitoring the VLAN

Could you try running sniffer and see whats happening with the actual packets ?


Re: VoIP Monitoring the VLAN

Are you using RSPAN? You will not get this working without configuring RSPAN. Fortunately the 4006 supports it so you will be ok.

New Member

Re: VoIP Monitoring the VLAN

Thanks, however, it's running Cisco IOS and not CAT OS. Cisco IOS will not support RSPAN until a future release.


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