Quick installation (legacy)

This document briefly describes the steps needed to install OpenVZ on your machine.

This document is also available in the following languages: French, German.

OpenVZ consists of a kernel, user-level tools, and VE templates. This guide tells how to install the kernel and the tools.

Contents

Requirements

This guide assumes you are running recent release of Fedora Core (like FC5) or RHEL/CentOS 4. Currently, OpenVZ kernel tries to support the same hardware that Red Hat kernels support. For full hardware compatibility list, see Virtuozzo HCL.

Kernel installation

Note: In case you want to recompile the kernel yourself rather than use the one provided by OpenVZ, see kernel build.

Get the kernel binary RPM from the Download » Kernel page, or directly from download.openvz.org/kernel, or from one of its mirrors. You need only one kernel RPM so please choose the appropriate one depending on your hardware.

Next, install the kernel RPM you chose:

rpm -ihv ovzkernel-name*.rpm

Note: rpm -U (where -U stands for upgrade) should not be used, otherwise all currently installed kernels will be uninstalled.

Configuring the bootloader

In case GRUB is used as the boot loader, it will be configured automatically: lines similar to these will be added to the /boot/grub/grub.conf file:

title Fedora Core (2.6.8-022stab029.1)
       root (hd0,0)
       kernel /vmlinuz-2.6.8-022stab029.1 ro root=/dev/sda5 quiet rhgb vga=0x31B
       initrd /initrd-2.6.8-022stab029.1.img

Change Fedora Core to OpenVZ (just for clarity reasons, so the OpenVZ kernels will not be mixed up with non OpenVZ ones). Remove extra arguments from the kernel line, leaving only the root=... parameter. The modifed portion of /etc/grub.conf should look like this:

title OpenVZ (2.6.8-022stab029.1)
        root (hd0,0)
        kernel /vmlinuz-2.6.8-022stab029.1 ro root=/dev/sda5
        initrd /initrd-2.6.8-022stab029.1.img

Configuring

Please make sure the following steps are performed before rebooting into OpenVZ kernel.

sysctl

There is a number of kernel parameters that should be set for OpenVZ to work correctly. These parameters are stored in /etc/sysctl.conf file. Here is the relevant part of the file; please edit it accordingly.

# On Hardware Node we generally need
# packet forwarding enabled and proxy arp disabled
net.ipv4.ip_forward = 1
net.ipv4.conf.default.proxy_arp = 0
# Enables source route verification
net.ipv4.conf.all.rp_filter = 1
# Enables the magic-sysrq key
kernel.sysrq = 1
# TCP Explict Congestion Notification
#net.ipv4.tcp_ecn = 0
# we do not want all our interfaces to send redirects
net.ipv4.conf.default.send_redirects = 1
net.ipv4.conf.all.send_redirects = 0

SELinux

SELinux should be disabled. To that effect, put the following line to /etc/sysconfig/selinux:

SELINUX=disabled

Conntracks

In the stable OpenVZ kernels (those that are 2.6.8-based) netfilter connection tracking for VE0 is disabled by default. If you have a stateful firewall enabled on the host node (it is there by default) you should either disable it, or enable connection tracking for VE0.

To enable conntracks for VE0, add the following line to /etc/modules.conf file:

options ip_conntrack ip_conntrack_enable_ve0=1

Note: in kernels later than 2.6.8, connection tracking is enabled by default

Rebooting into OpenVZ kernel

Now reboot the machine and choose "OpenVZ" on the boot loader menu. If the OpenVZ kernel has been booted successfully, proceed to installing the user-level tools for OpenVZ.

Installing the utilities

OpenVZ needs some user-level tools installed. Those are:

vzctl

A utility to control OpenVZ VPSs (create, destroy, start, stop, set parameters etc.)

vzquota

A utility to manage quotas for VPSs. Mostly used indirectly (by vzctl).

Download the binary RPMs of these utilities from Download » Utils, or directly from download.openvz.org/utils, or from one of its mirrors. Install them:

rpm -Uhv vzctl*.rpm vzquota*.rpm

If rpm complains about unresolved dependencies, you'll have to satisfy them first, then repeat the installation.

When all the tools are installed, start the OpenVZ subsystem.

Starting OpenVZ

As root, execute the following command:

/sbin/service vz start

This will load all the needed OpenVZ kernel modules. This script should also start all the VPSs marked to be auto-started on machine boot (there aren't any yet).

During the next reboot, this script should be executed automatically.

Next steps

OpenVZ is now set up on your machine. To load OpenVZ kernel by default, edit the default line in the /boot/grub/grub.conf file to point to the OpenVZ kernel. For example, if the OpenVZ kernel is the first kernel mentioned in the file, put it as default 0. See man grub.conf for more details.

The next step is to prepare the OS template: please continue to OS template cache preparation document.