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Linux/CentOS templates in VMware ESXi

I am sure there are other posts like this out there, but last time I checked, there wasn't much info on this, so here goes.

I want to use kickstart to deploy virtual machines.  Rather, wanted.  Forgot that kickstart requires ethernet right off the bat, and the vmxnet3 NIC doesn't work until vmware tools is active.  I could use the E1000, but then I'm still having to delete/reconfigure after the fact.  This method means VM rollouts that are probably just as fast as kickstart, and possibly a little easier.  I could probably write a script to do the hostname/network cleanup as well.

Anyways, here's my attempt at vCenter templates for CentOS.  This is pulled from my wiki, posted here for searchability.

CentOS vCenter template creation

  • Created a new VM and gave it 1cpu/1GB RAM/40GB thin drive.
  • Installed CentOS 6 x86_64.
  • I configured LVM - do so according to your wishes. (I specifically added LVs for /var/log, /var, /tmp, and /home)
  • Set passwords, timezone, etc.
  • Once done, I installed VMware tools, deleted temp stuff afterwards
  • Configured the networking and gave the template IP (designated in my IP list)
  • Shut down the VM
  • Removed the VMware tools ISO and floppy drive
  • Created a template out of this VM (convert to template)

One last item I left out - remove the ethernet adapter.  Why?  If you clone this VM, it'll keep the mac, and confuse the new VM.  There is a process to fix it, but it might be less work to just add a new adapter.

Process for fixing a cloned ethernet adapter is move the ifcfg-eth0 file to ifcfg-eth1, edit the file and change the device name to eth1 and the MAC address to suit, then edit the IP to match the new VM.  Change the /etc/sysconfig/network file to suit the hostname.  Reboot the host.

A few items I left off are doing something with SElinux and iptables.  For my lab I've disabled them and will eventually work on getting them functional.  At the moment, that's low priority.


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