Redundancy over multiple SRST Router

[william.ong]

Hi,

For maximum redundancy, can I deploy multiple SRST routers using HSRP/VRRP/GLBP? Each of the SRST router will have E1 lines. Tks!

[Aaron Harrison]

Hi

Yeah, sure. I've deployed multiple SRST routers together to increase the max handset count, but the principal for this should be the same.

Phones would register to the HSRP master, or probably randomly register to the GLBP pair.

You would need to set up dial-peers on each router so that:

1) Incoming calls from the PSTN could be routed to whichever gateway the IP phones are registered to.

2) Calls between IP phones registered to different gateways can reach the phones.

The best way to do this is to set up the gateways identically in terms of call-manager-fallback, PSTN dial-peers, translations etc.

Then add dial-peers to each, pointing at the other gateway (here the example assumes that extensions are number 1000-1999):

dial-peer voice 100 voip

destination-pattern 1...

session target ipv4:

This would have the effect that calls made to an IP phone extension 1234 would go direct if it is registered to the local gateway, if it is registered to the other gateway the next less-specific match is the dial-peer that points to that gateway.

Regards

Aaron

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[william.ong]

Hi Aaron,

It works with GLBP? That will be very useful since I can have fewer SRST phone licenses per gateway.

Tks!

[Thomas Dillingham]

You should use a corlist to prevent a call routing loop, if the GW is also configured as a CUBE.