Multiple session target IP addresses in a dial peer

[Andrew West]

Hey everyone,

My integration is back to a Nortel PBX which has both an active an inactive core and each of those obviously has a different IP address.

I currently have dial peers that point back to the active core which look like this:

dial-peer voice 2 voip

description Outgoing calls to XXXXXX

destination-pattern 12345

session protocol sipv2

session target ipv4: 1.1.1.1

dtmf-relay rtp-nte

codec g711ulaw

no vad

I have about 6 of these plus a corresponding SIP trunk built on the CUCM. I know on that I can add the second IP address on the CUCM trunk without much issue but my question is about the dial peers on the CUBE.

Is their a way to handle multiple session IP's within 1 dial peer? I dont want to have to manually change each dial peer whenever the the active cores swap on the Nortel so if I could handle that in a programmtic way that would be ideal.

[paolo bevilacqua]

No, there is no way. But you can summarize patterns to lesses the number of dial peers, and with latest IOS, also have multiple pattern under one same DP.

[Michael Gerrard]

Three ways spring to mind:

1) Use IP SLA and EEM to ping the primary PBX, and when it goes down you would get the EEM to change the preference statements round.

2) More simple I guess, is to just have multiple dial-peers with a preference statement, and ensure that the h225 connection establish timeout under voice service voip is minimal (3 seconds) - so that if the primary pbx dies, the router will then just pick the next dial-peer that matches the same destination-pattern.

If you want to do it all in one dial-peer then the closest I could probably come up with us to use session target dns. You then add a couple of A records onto DNS with the same name (Lets call the A record pbxservice), but have the two different IP addresses. The problem with this is that it's not terribly programmatical, and brings the complexity of DNS into the mix.

HTH!

[Fedor Solovev]

Hi.

http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/voice/dialpeer/configuration/15-mt/vd-15-mt-book/multiple-server-groups.pdf

this can be done with voice class server-group instead of session target ipv4:

[Tagir Temirgaliyev]

yes, beginning from IOS 15.4