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.

4300 Series Routers Bugs

Having deployed a number of the new 4331 routers to replace 2800 series routers as voice gateways, there's been some quirks...

The first being that unicast music on hold stopped working. Identical configuration to the 2800 routers, but PSTN callers just hear silence. Eventually found that setting the CallManager service parameter Duplex Streaming Enabled to true fixes this problem:

I also hit a nasty bug in that 4000 series IOS XE releases 3.15.0, 3.15.1 & 3.16.0 aren't fit for purpose as voice gateways, whenever the router reloads the dial-peer configuration (along with NBAR & some ACLs) disappears. Why these versions aren't deferred releases yet I don't know?!

UPDATE: Now to cap it all off the 4300 series is undergoing a recall.