We are using ESX 3.5 and are considering the use of templates to deploy W2008 servers in our production environment.
The production environment is about 30 sites and will contain Active Directory 2008 DC's, Branch Office RODC's, File/Print/DHCP Servers. Each site will have an ESX 3.5 host.
We have experimented with templates and have had issues with network interface settings reverting back to the original source guest settings.
Another issue is forgetting to regenerate the SID when deploying the template.
These issues have caused us to lose confidence in the use of templates at all, since we really can't use them for DC's anyway, and the amount of time it takes to install and configure w2008 from scatch (we have written procedures for this) is only about an hour.
Will anyone please share their experience with the use of templates?
Does anyone use templates for deploying vmware guests into their production environment?
What problems have you had and how did you resolve it?
If you tried to use templates but abandoned their use, what was the reason?
Any responses are appreciated.
thanks in advance.
To be honest I can't imagine not using templates in a production environment. I recognize you have a standard build process but I'd much rather rely on automation to ensure a consistent Windows image across all of my virtual machines.
It sounds to me like the issues you had before may have been caused by the fact that you weren't using Guest Customizations. That process will essentially let you automatically Sysprep the machine, cleaning out the SID and letting you do things like join it to the domain, name it based on the virtual machine name, etc. The nice part about using it with Windows 2008 is that Sysprep is built into Win2k8, so you don't have to copy any files to your vCenter Server to make this work.
In environments where VMs are buil/destroyed on a regular basis (dev/test\/research), I find that templates save a huge amount of time. I can simply deploy from template, login to the VM when it's done and assign it an IP address and I am essentially done. I can get a VM fully deployed, configured, patched, and ready to go in probably 15-20 minutes tops.
When it's time to update the template VM with new Windows critical updates, I can quickly convert it back to a VM and run the updates and then just convert it to a template again. This is a hueg time saver, as trying to apply 30-40 Windows updates can greatly slow down the total time to deploy a VM if you're building a Windows image from scratch.
I'd really recommend looking at templates and Guest Customizations again. I think if you start using the Guest Customizations you'll start to see the power and time saving aspects of templates. Good luck!