fast busy on IP trunk

[donayaan]

We are getting "fast busy" on a IP trunk between our two main sites. What do i check to troubleshoot?

i see all Trunk members inservice/idle on both sides and not in maintenance mode.

Shall i trace the call and check denial event?

I assume telco is not involved as this is IP trunk?

Am i correct?

Thanks.

 

[esch1004]

The telco is not incolved. You can do a list trace TAC and see what it tells you. That's usually a good place to start. Also check the port numbers on the signalling group for on both sides.

 

[dufus2506]

You might also check to see if you have network or routing issues. Being connection-less, an IP trunk can only reliably tell you about it's state on it's own end. It won't know that the other end is unreachable until someone tries to place a call.

Carpe dialem! (Seize the line!)

 

[donayaan]

so if network link(WAN) is down, will fast busy occur on tie trunk?

 

[donayaan]

i did trace TAC, i get same denial event 1190, any ideas?

 

[donayaan]

user can get "dialtone"...

 

[dufus2506]

Yes, if the WAN is down the system will return a fast busy.

If you've ever checked out the trunks when they're in use, you'd see traffic on say, trunk number 5 on one side, but on number 12 on the other side. They're not mapped one to one. They're assigned and dropped as needed. But if there's a WAN failure in between, the PBX won't know until a call is placed.

As long as there is a live ethernet connection on the C-lan card associated with the IP trunk group, you'll see in-service, idle trunks.

Carpe dialem! (Seize the line!)