New Subscriber Installation Failing With 10.5 After DRS Restore

I recently encountered this bug in 10.5 which breaks the ability to install subscribers after a DRS restore. As Cisco's official P2V method is to do a DRS backup from the physical machine & then a DRS restore to an identically configured virtual machine, this largely applies to upgrade projects where you have to P2V CUCM as it was running on a physical MCS 7800 series server.

With the 10.5.2.12901 upgrade I was working on, the subscriber installation would get stuck after validating network connectivity to the publisher with a very helpful error message:

There is a bug report (CSCus35964) for this & a patch ciscocm.Fix_DRS_Recovery_v1.0.k3.cop.sgn that must be installed on the publisher, then the publisher rebooted.

UCCX Editor Script Repository and Reactive Debugging Not Working

In UCCX 10.0 Cisco decided to change the way UCCX works so that hostnames not IP addresses are used for inter-server communication. The UCCX Editor was also changed to use hostnames, resulting in the odd situation where you can authenticate against the UCCX server by IP address, but browsing the script repository or using reactive debugging doesn't work. This is because the UCCX Editor will try to use the hostname of the UCCX servers, if the DNS A records don't exist or you're connected via a VPN without correct DNS configuration then the DNS resolution will fail & these features won't work. The error message provided is pretty vague on this, for example if you try to use reactive debugging it will get stuck with the message "Engine hostname list is empty. Check the ldap for enabled unified ccx engines".
The solution is to kludge it by editing your local hosts file to contain the hostname & FQDN of the UCCX server(s). On Windows edit the file C:\Windows\System32\drivers\etc\hosts, example entries below:

10.15.0.5      perry
10.15.0.5      perry.somewhere.com

Unity Connection Intra-Site Networking Stalled

In some situations when adding server(s) to Unity Connection's intra-site networking, replication can get stuck and constantly show errors on the Voice Network Map. Symptoms include not seeing other server's partitions, search spaces, users, distribution lists, etc. Looking at the traces for Connection Digital Networking Replication Agent service shows many entries like "18:34:13.772 |20016,StalledReplicationDetector,,-1,-1,Detected stalled replication sending to location <location name>. Waiting for acknowledgment of USN <number>. This situation may indicate network connectivity problems."
Follow these steps to get replication unstuck:

Remove the stuck servers from Locations via "remove self from site".

On all servers restart the following services:
Connection Digital Networking Replication Agent
Connection SMTP Server

Add the servers back, don't forget to put in the Connection Location Passwords on all servers & activate the Connection Digital Networking Replication if necessary.