Installing And Using OpenVZ On Ubuntu 8.04 LTS Server

Version 1.0
Author: Falko Timme

In this HowTo I will describe how to prepare an Ubuntu 8.04 LTS server for OpenVZ. With OpenVZ you can create multiple Virtual Private Servers (VPS) on the same hardware, similar to Xen and the Linux Vserver project. OpenVZ is the open-source branch of Virtuozzo, a commercial virtualization solution used by many providers that offer virtual servers. The OpenVZ kernel patch is licensed under the GPL license, and the user-level tools are under the QPL license.

This howto is meant as a practical guide; it does not cover the theoretical backgrounds. They are treated in a lot of other documents in the web.

This document comes without warranty of any kind! I want to say that this is not the only way of setting up such a system. There are many ways of achieving this goal but this is the way I take. I do not issue any guarantee that this will work for you!

1 Change The Default Shell

/bin/sh is a symlink to /bin/dash, however we need /bin/bash, not /bin/dash. Therefore we do this:

ln -sf /bin/bash /bin/sh

2 Disable AppArmor

AppArmor is a security extension (similar to SELinux) that should provide extended security. In my opinion you don't need it to configure a secure system, and it usually causes more problems than advantages (think of it after you have done a week of trouble-shooting because some service wasn't working as expected, and then you find out that everything was ok, only AppArmor was causing the problem). Therefore I disable it.

We can disable it like this:

/etc/init.d/apparmor stop
update-rc.d -f apparmor remove
apt-get remove apparmor apparmor-utils

3 Installing OpenVZ

OpenVZ is available in the Ubuntu repositories. To install the OpenVZ kernel, run:

apt-get install linux-openvz

Now we install some OpenVZ user tools:

apt-get install vzctl vzquota

Open /etc/sysctl.conf and make sure that you have the following settings in it:

vi /etc/sysctl.conf

[...]
net.ipv4.conf.all.rp_filter=1
net.ipv4.icmp_echo_ignore_broadcasts=1
net.ipv4.conf.default.forwarding=1
net.ipv4.conf.default.proxy_arp = 0
net.ipv4.ip_forward=1
kernel.sysrq = 1
net.ipv4.conf.default.send_redirects = 1
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.eth0.proxy_arp=1
[...]

If you need to modify /etc/sysctl.conf, run

sysctl -p

afterwards.

The following step is important if the IP addresses of your virtual machines are from a different subnet than the host system's IP address. If you don't do this, networking will not work in the virtual machines!

Open /etc/vz/vz.conf and set NEIGHBOUR_DEVS to all:

vi /etc/vz/vz.conf

[...]
NEIGHBOUR_DEVS=all
[...]

Finally, reboot the system:

reboot

If your system reboots without problems, then everything is fine!

Run

uname -r

and your new OpenVZ kernel should show up:

root@server1:~# uname -r
2.6.24-19-openvz
root@server1:~#