Cascading ARS

[kflounders]

I have two 500s at 4.2.17 SCNed over Fiber link. PRI in each and back up pots as well. Can I have the ARS go Local PRI, Remote PRI, and then Local Backup Pots?

Here is my thinking:

I initiate a call from site A, the PRI is down so my call goes over IP trunk to site B. The site B PRI is down, so do I now follow the site B ARS and have it put me in a loop, or do I go out via the pots in site A that is the backup to my backup.

 

[IPXTech]

Should work OK.

Site A has a backup ARS that has

Code: 1N
Number: 71N
Line Group ID: To Site B

Site B has a shortcode 7N that points to a seperate ARS table to go over local PRI. That ARS then has a backup ARS like this..

Code: 1N
Number: 61N
Line Group ID: To Site A

And then create a shortcode 6N to point to yet another ARS that has 1N going over local copper.

Hope it makes sense. I haven't tried it myself but theoretically that should work I think.

 

[IPXTech]

I should clarify, Site B should have a completely seperate ARS for the backup calls coming from Site A to prevent it from getting into a loop.

 

[kflounders]

What appears to happen live is that the calls go to site B, it sees that there is no PRI avaialble there and just sits there in "waiting for line" it doesn't fail back over to POTs on site A.

 

[CarGoSki]

Since your backup is a IPtrunk you may want to build a duplicate IP Trunk between sites using unique trunk group numbers. You will be able to build a dedicated failover and ars at site B that will not conflict with site B's normal routing.