ITG timeout

[maggier]

Hi there,

We have an issue whereby, when we 'lose the network' for say 30 secs, it takes approx 10 minutes for voice to resume across the network (shared data and voice) link or to failover to out BT backup voice link.

We have pinned this down to the ITG cards (we have 3 per site - 96 channels at one site, 80 at the other) disabling their ports when they cannot see eachother after a period of time, then enabling the ports again.

Does anyone know if the time before they time out can be increased. Our network guys are working to reduce the failover time to 20 secs, but if we are unable to adjust the ITG timeout it will not be of much benefit,

any ideas or thoughts would be much appreciated.

Cheers
Mags

 

[johnpoole]

you don't have a timeout that i have ever heard about, i've seen a simular problem on network conjestion. high traffic times causing that problem. that site was a banking customer, they lost voice during closing. the right solution would have been to buy more bandwidth (wan) but the sales engineer had sorta killed that with a few facts that were not exactly acurate.. they bought the system to save money, increasing monthly was not something we could suggest... they took the system out and went back to tdm voice...

john poole
bellsouth business
columbia,sc

 

[maggier]

ok thanks,

it is a strange one, we are totally over capacity using only 50 -55 channels at our busiest times on our itg trunks and congestion on the network isnt a problem for us, though it has been in the past.

It just seems like itg1 tries to see itg2, say for 20 secs, say every 5 seconds, then it decides and says hang on, the network just isnt there, i'll stop trying, then it looks like it tries at bigger intervals after that because it looks like 5 mins later it looks again, sees the network reenables the ports and we are up and running again

 

[dlesap]

ITG have a TTL (Time to live) parameter which is the acceptable time not to see other side. It guess that your problem. If ITG doesn't see other side, your network have to be qualified for QoS.

After system is up and running without congestion, calls doesn't choose to use that way before QoS has finished his job and says "OK you can go!"

Details could be found in NTPs engineering book. I know that's hard to eat, but you will get a good understanding after that.