I have a site with two routers (voice gateways) with an ISDN PRI connected to each of them. I had one of the PRIs working for 2 months (connected to one gateway) and recently we have added the second PRI (on the second gateway). IP vice, the gateways are running iBGP between each other and can get to each other and both are active routers (no HSRP). I had one gateway in my route group since only one of them was doing voice and just recently I have added the second gateway (H323) into the route group (Distribution Algorithm being 'Top Down'). So right now the route-group has two gateways. Basically the idea is to make use of the second gateway and PRI when the first PRI goes down. When I tested bringing the first PRI down, phones could not dial out or in. I got a chance to reset the Route-Group and Route-List on the CM, but did not reset the route-patterns where these route-list is applied. Is a reset on the phones or route patterns needed to make it work? I just want to explore my options before I try this again.
One other question in my mind is, even if the first PRI goes down, the gateway would still be up and registered with the CM. How exactly does the route-group make use of the second gateway?
Any documentation lead is also appreciated.