Multiple Call Manager environments via a single gateway?

nbernhardt · ‎11-27-2007

I recently started working for a small commercial datacenter. My expertise is in Cisco IPT, but this issue gets into an area I'm not very well versed in.

The question is, how would I architect my environment to allow two separate Call Managers (Business Editions), which we have co-located in our datacenter, to be able to utilize a single AS5400 Universal Gateway? We have 4 PRI circuits going into the AS5400 as of right now.

The solution is being sold with us providing the colocation and the termination of the customers PRI. However, our datacenter manager decided to forego purchasing a ISR router to do terminate the PRI into, in stead he wants to leverage our AS5400 to do the job.

On top of this, we'll have our own Call Manager installed shortly that will need to be able to utilize the AS5400 to gain access to the PSTN.

Keep in mind that neither Call Manager can be allowed to be aware of the state of the other one. These have to be completely sovereign installations and configurations.

My question is what's the best option here? MGCP doesn't seem suited to the task, so that (in my mind at least), leave configuring H.323 or SIP trunks. Does this seem appropriate, or is there some means to accomplish the same thing with MGCP (would I even want to if I could).

Originally we were only going to be using the AS5400 for our own Call Manager, so we were going to use MGCP.

Thoughts?

dtran · ‎11-27-2007

Hi Nick,

When you say two separate CallManagers, I am assuming you're referring to two separate CallManager clusters. I think what you're trying to accomplish is doable assuming IP connectivity between the AS5400 gateway and the 2 CallManager clusters is a given.

Here is what I have in mind.

I think H.323 will do the job, you'll have to configure two H.323 source addresses (one for each CCM cluster) in the AS5400 gateway and then add an H.323 gateway in each CCM cluster using the H.323 source address configured for each CCM cluster. I am assuming you're already familiar with Route Pattern, CSS, Partition .. etc.. that need to be configure CCM to route calls.

Hope that helps !!

Danny

I think

nbernhardt · ‎11-27-2007

Yes, these are two separate CallManager clusters, except that they're not clusters because CallManager 6.0 Business Edition runs on a single box, no pub/sub setup, so no actual clustering to speak of in this case.

Yes, I'm familiar how to do all the route patterns, CSS and partitioning.

I think I'll try to setup both H.323 and SIP trunking. The reason is that we're going to also have a UC520-32U for demo purposes, and that doesn't really have an option to use H.323 (as far as I'm aware). Either way this should be interesting.

paolo bevilacqua · ‎11-27-2007

Sure you can have H.323 and SIP even concurrently on the UC520. Consider, certain CCME features, work only on H.323.

bigcappa1 · ‎11-28-2007

Nick,

This should not be too much of a problem Like the other posts say. The main concern I suppose would be use of you dial plans within the datacentre. If they are overlapping then this is where you will have to start being clever with the route patterns, partitions etc as well as configuring the voip peers correctly. I would uses H.323 as i feel you can see more of whats going on on the voice gateway.

Let us know how you got on

Paul