Tracing voice calls on the voice VLAN?

[d.anthony.hadley_2]

How can you make sure your trace route takes the voice vlan throughout the network to retrace problems with voice quality? I'm troubleshooting a voice quality issue for a customer. The call goes from a voice gateway, 3745, through three 3524s, two other 3745s, a 6509, and two 4006s. The network uses separate voice and data VLANs but not all devices are configured with VLANs. So, how can I make sure the trace from the voice gateway takes the voice VLAN to the Unity server? thanks.

[rbradfield]

too many unknowns here

1) is the unity server on the voice vlan

2) where is the L3 switch

3) is everything interconnected by trunks

4) do the 3745s do routing

Ideally there would be one layer 3 switch involved do all the routing if there are multiple routers with multiple paths to the destination, then you will have to use route maps to direct the flow of traffic through the required subnets.

HTH

Richard

[d.anthony.hadley_2]

Thanks for the response. The Unity server is on the voice VLAN.

The flow goes from Unity to a 3524 switch. The port it's plugged in to is in the voice vlan. It goes from there out a Gig port (not in any VLAN) to a 4006, where the voice VLAN is active but no specific ports are in it. Then, to another 3524 switch, which has the voice VLAN configured but no specific ports are in it. Then in to a 3745 where no VLANs are configured. From there it goes to another 3745 where no VLANs are configured (it does have an ATM "voice" circuit configured with a service policy on it that goes to the main site). Finally, it goes to the voice gateway, a 3725 with a PRI, where no VLANs are configured.

The route back from the voice gateway to the Unity server takes a more round-about path and crosses several different VLANS in the process. This is a regular trace. How do I know what path the voice traffic takes?

The 3700s and the 4006s do the routing. The layer 2 switches are connected by gig ports. I hope this helps. Thanks.

[rbradfield]

you say:

"It goes from there out a Gig port (not in any VLAN) to a 4006" <<

also you say:

Then in to a 3745 where no VLANs are configured. From there it goes to another 3745 where no VLANs are configured <<< if there are no vlans where is the router that routes from the voice vlan to the 3745 lans.

did you mean to include the trace?

[mciarfello]

What quality problems are you having and what does the QoS configs look like on each device along the way? Have you done a sniffer capture to make sure the DSCP markings are still present when the packet gets to the other end? For example, span the Unity port to a sniffer, capture packets, lookup the IP address for a phone you left a test message with and make sure all the Qos (DSCP) markings are there.