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dual 2811 with dual isdn30s

We have recently deployed 2x 2811 running CISCO CME. Both boxes have an E1/T1 module in them which will be connected to the local PSTN for the Telephones. Is there a way of tracking these interfaces between the Routers so that if one of the E1’s goes down on one Router all of the phone calls know that they need to jump across to the E1 on the other Router for their way out??? Both E1’s are provided by the same PTT so all of the Dial Plans on both Routers will be the same…

Super Bronze

Re: dual 2811 with dual isdn30s


Yes - presuming that the two CME routers are reachable via IP and have sufficient bandwidth/QoS guarantees..

You will have dial-peers for PSTN numbers, maybe like this:


dial-peer voice 2 pots

description ** E1 PRI pots dial-peer **

destination-pattern 9T

port 0/0/0:15

Change it to have preference 1 in it:

dial-peer voice 2 pots

description ** E1 PRI pots dial-peer **

destination-pattern 9T

preference 1

port 0/0/0:15

Then add another dial-peer

dial-peer voice 10 voip

destination-pattern 9T

preference 2

session-target IPv4:

dtmf-relay h245-alphanumeric

Configure the other CME to do the same, but send calls to CME1 if the PSTN fails.



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Aaron Please remember to rate helpful posts to identify useful responses, and mark 'Answered' if appropriate!
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