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New Member

SRST not to use backup WAN link

Just wanted to know on an MGCP SRST setup, what tcp/udp ports do you need to block on a backup WAN link if you want to activate SRST when main link is down. We blocked tcp 2000 on the backup link but its not working. The phones go into fallback mode but we are unable to dial out. Only works when both WAN links are down. Do we need to block mgcp udp port 2427?


Re: SRST not to use backup WAN link

You can do that, or block connectivity to the call manager IP addresse all together. What I do is put in a blackhole host route to null0 for the call manager IPs when testing SRST/MGCP Fallback.

Make sure you have MGCP fallback also configured so the voice ports controlled with MGCP fallback to H.323.

New Member

Re: SRST not to use backup WAN link

Thanks Eberqquist. Probably just try with blocking mgcp first and if any issues arise then block all access to the CMs.

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