In a recent Cisco Expressway deployment I ran into a bug that is worth mentioning to the community.
I usually recommend naming the Expressway-E server with the enterprise’s standard naming convention. Then for the _collab-edge SRV record, create a generic name on the public Internet to point to the Expressway-E server. Normally this is not a problem, however the bug CSCuo83458 complicates this.
The official conditions of the bug is “The Expressway-E server is configured with a hostname and/or domain name which does not exactly match what is present in the _collab-edge SRV record.” The symptom is “Clients unable to register via Mobile and Remote access via XMPP or SIP. Jabber clients may show an error message of ‘Unable to connect to server’.”
What is comes down to is that the Expressway-E name, internal DNS records, and the _collab-edge SRV must be exactly the same. If they are not, Jabber will not be able to connect.
There is no fix for this bug as of this writing. The workaround is to name the Expressway-E the same as the SRV record. Until this is fixed, my recommendation to my clients is to name the Expressway-E the generic name on the public Internet. Then once this bug is fixed, the hostname of the Expressway-E can be changed.
Bug ID: https://bst.cloudapps.cisco.com/bugsearch/bug/CSCuo83458/