This article describes how you can update an existing precreated Debian or Ubuntu template. 

===== Creating/configuring a temporary container =====

  - Create a container based on the template you want to update. for this you can use the GUI.
  - Then enter the asked values and start your container. 


===== Updating =====

  - Login in the Proxmox node where the VPS was created.
  - Check your container's ID (check CTID column) with the following command: <code># vzlist</code>
  - Enter the container: <code># vzctl enter [CTID]</code> 
  - Configure the repositories.
  - Update metadata and install updates: <code># apt-get update && apt-get upgrade</code>
  - Cleanup: <code># apt-get clean && apt-get autoclean</code>
  - Clean unused log files, .bash_history etc, then exit from a container: <code># exit</code>
  - Stop a container.


===== Packing a new template cache =====

To complete this task you can create a new tarball:
<code>
# cd /var/lib/vz/private/[CTID]
# tar --numeric-owner -czf /var/lib/vz/template/cache/debian-7.8-mininal-i386.tar.gz .
</code>

Where [CTID] is the container's ID.

Another way is backup your container using the GUI and move the backup file to /var/lib/vz/template/cache/. Remember select the compression method: //GZIP (good)// and Mode: //stop//.