MRA with several CUCM clusters and domains,is it possible without ILS?

[david.alfaro1]

Hello dears,

I hope you are doing well.

We have a MRA deployment, with three CUCM clusters each one with a different domain.

For several restrictions, we had to add the SRV's and A records to the /tandberg/etc/dnsmasq.conf.d/ folders, the hosts.conf and srv.conf files, because we are unable to get DNS servers which solves these records.

Now, since there are three different CUCM clusters integrated with the MRA deployment, also we have restrictions to deploy ILS. So we would like to know if someone has ever tried to add the cluster names in the expressways, in the same manner as we add the SRV's and A records in the expressways. In other words, I mean, does it exist a way to add the CUCM cluster names in the expressways without using ILS?

kind regards,

[Roger Kallberg]

Adding CM clusters into Exp-C in a MRA setup has no connection with running ILS between the clusters. ILS is used to distribute the home cluster information for users that the MRA function use when doing the UDS lookup of the connecting user.

[Maren Mahoney]

To add to what @Roger Kallberg wrote, in a multi-cluster environment with Jabber deployed (whether MRA is in use or not, and whether you have one or multiple domains) you must run ILS (or the old "Cluster View") so that Home Cluster information can be exchanged between the clusters.

As a separate step, deploying MRA in a multi-domain multi-cluster environment is well-documented. The biggest trick is the certificates, but that is included in the documentation. But your post suggests you are on top of that.

Let us know if you have additional questions.

Maren

[Nithin Eluvathingal]

For this requirement, you need ILS. I have a customer site that has 12 CUCM clusters using one cluster of Expressway Pair for MRA, and this relies purely on ILS .

We encountered an issue with ILS as two Cluster had the same peer ID. This happened because they were built by PCD using the same source cluster. As a result, the MRA was failing intermittently.

In our scenario, all 12 clusters belong to the same domain. The Expressway will direct the request to any CUCM cluster in the list. The home cluster lookup will fail if ILS is not set up.

In your situation, as they all are in different domains, it’s uncertain whether Expressway will route the request based on the domain to the corresponding clusters.