Call stay for 4 minutes when wan lost

[shouyisun]

Centralized CCM . Remote office use H323 and SRST.

When WAN lost, we found the active call can stay 4-4.5 minutes then call dropped.

If WAN restored, call established during the SRST mode will stay for ever.

Anybody know why it only can last around 4 minutes. Is something related with the H225 idle time?

Thanks

[benng]

Please see CSCdx26761.

You're on the right track. Currently, TCP keepalives are enabled for established h225 sessions. When the WAN goes down, TCP keepalives will be lost between the SRST GWY and the CCM, the SRST gwy will terminate active calls after about 4 minutes.

Fix for this requires a new CLI which make this timer a configurable h323 parameter.

-ben

[adignan]

I would suggest moving to MGCP. This will allow those same calls to stay up.

[Sascha Monteiro]

but on a MGCP gateway with E1 PRI and SRST,

the call gets dropped when WAN disconnects...

[annayuzhao]

I had same issue when use MGCP. The reason for that is Cisco use Q931 haulback to CCM, when wan lost Q931 can't be maintained through GW. Call drops. Having said that, from call preservation point MGCP even worse than H323?Any other comment?

Thanks

[shouyisun]

Which version support this new command? Has it been released? The bug shows no workaround now. Thanks