Updating Debian template
This article describes how you can update an existing precreated Debian or Ubuntu template. The procedure is pretty easy.
Contents
Creating/configuring a temporary container
First, you need to create a container based on the template you want to update. Here is an example:
[HN]# vzctl create 555 --ostemplate debian-4.0-i386-minimal
Next, you want to specify an IP address and a nameserver:
[HN]# vzctl set 555 --ipadd x.x.x.x --nameserver y.y.y.y --save
You can get the value of nameserver from your /etc/resolv.conf. Your container should have an Internet access, so you either supply a public IP, or see using NAT for container with private IPs for information about how to use private IP and NAT.
Then start your container:
[HN]# vzctl start 555
Finally, check that Internet is working from inside your container:
[HN]# vzctl exec 555 ping -n -c 1 www.ru
Update
Enter the container:
[HN]# vzctl enter 555
Update metadata and install updates:
[container]# apt-get update && apt-get upgrade
Cleanup:
[container]# apt-get clean [container]# > /etc/resolv.conf
Clean unused log files, .bash_history etc, then exit from a container:
[container] # exit
Stop a container, remove its IP:
[HN]# vzctl stop 555 [HN]# vzctl set 555 --ipdel all --save
Packing a new template cache
Now, rename the existing template cache:
[HN]# mv /vz/template/cache/debian-4.0-i386-minimal.tar.gz{,-old}
Change to VE folder:
[HN]# cd /vz/private/555
For newer OpenVZ kernel and ploop VE: (mount VE)
[HN]# mkdir /mnt/new_template [HN]# mount -t ploop /vz/private/555/root.hdd/DiskDescriptor.xml /mnt/new_template [HN]# cd /mnt/new_template
Now create a new tarball:
[HN]# tar --numeric-owner -czf /vz/template/cache/debian-4.0-i386-minimal.tar.gz .
For newer OpenVZ kernel and ploop VE: (unmount VE)
[HN]# umount /mnt/template
Clean up:
[HN]# vzctl destroy 555 [HN]# rm -f /etc/vz/conf/555.conf.destroyed
Test new template cache
First, compare the sizes of the old and the new template caches:
[HN]# ls -lh /vz/template/cache/debian-4.0-i386-minimal* -rw-r--r-- 1 root root 55M 2007-11-13 18:11 /vz/template/cache/debian-4.0-i386-minimal.tar.gz -rw-r--r-- 1 root root 53M 2007-08-31 02:46 /vz/template/cache/debian-4.0-i386-minimal.tar.gz-old
The sizes should not differ much.
Try to create and start container made from your new template:
[HN]# vzctl create 222 --ostemplate debian-4.0-i386-minimal [HN]# vzctl set 222 --ipadd 10.0.0.222 --save [HN]# vzctl start 222 [HN]# vzctl enter 222
Now execute a few basic commands to check container is fine. Examples are: ps axf, dpkg -l, etc.
Finally, clean up the testing container:
[HN]# vzctl stop 222 [HN]# vzctl destroy 222 [HN]# rm -f /etc/vz/conf/222.conf.destroyed