The need to clean up a cloned Virtual Machine
In working with a client recently I noticed that they are cloning virtual machines and it’s causing issues with their tool set. This really came to light when working with their XenApp servers. The Citrix team was building servers loaded with apps to create a template that could be cloned to create the other servers in a application pool. The issue with this is that the team was using existing servers already in production that already had the tools installed on them. The problem came to light with issues from the tools used to protect and monitor the virtual machines. This would not be an issue with standard OS templates already created that would have the tools added after the cloning process.
When cloning the virtual machine there are still a lot of registry entries left over with the old server name for tools like Opsware, McAfee and an asset mgmt application. These old registry entries would cause the new VM to knock the old VM out of the tools console and cause issues with reporting and management of the source server. For example Opsware would start talking to the newly cloned server thinking it was the source server and this would leave the source machine not in the patching scheduled.
To clean this up it was necessary to uninstall these tools from the new virtual machine then go back through the registry and clean up any entries that referenced the old server name. Then reboot the server and reinstall the tools. This will clean up the issues and allow everything to work without conflicting with the source server.
So for future requests of this type they have agreed to either use a base OS build and load applications on by hand or create their Citrix template with applications and clone prior to installing any monitoring applications. This will eliminate the issues that they had been experiencing.
About Brian Suhr
Brian is a VCDX5-DCV and a Sr. Tech Marketing Engineer at Nutanix and owner of this website. He is active in the VMware community and helps lead the Chicago VMUG group. Specializing in VDI and Cloud project designs. Awarded VMware vExpert status 6 years for 2016 - 2011. VCP3, VCP5, VCP5-Iaas, VCP-Cloud, VCAP-DTD, VCAP5-DCD, VCAP5-DCA, VCA-DT, VCP5-DT, Cisco UCS Design