Curx

"curx" aka Thorsten Schifferdecker

--//--

OpenVZ consists of a kernel, user-level tools, and VE templates.

This guide tells how to install the kernel and the tools on Debian and related Distribution like Ubuntu.

Requirements

Filesystems

It is recommended to use a separate partition for VEs private directories (by default /var/lib/vz/private/<veid>). The reason why you should do so is that if you wish to use OpenVZ per-VE disk quota, you won't be able to use usual Linux disk quotas on the same partition. Bear in mind, that per-VE quota in this context includes not only pure per-VE quota, but also usual Linux disk quota used in VE, not on HN.

At least try to avoid using root partition for VEs, because the root user of VE will be able to overcome 5% disk space barrier in some situations. This way HN root partition can be completely filled and it will break the system.

OpenVZ per-VE disk quota is supported only for ext2/ext3 filesystems. So use one of these filesystems (ext3 is recommended) if you need per-VE disk quota.

Repository setup

At the moment two different repositories are online at http://download.openvz.org :

Ola Lundqvist <opal@debian.org> --> apt-uri http://download.openvz.org/debian

Thorsten Schiffedecker <tsd@debian.systs.org> --> apt-uri http://download.openvz.org/debian-systs (Mirror of OpenVZ Repository from http://debian.systs.org)

Note: The next steps used the Repository http://download.openvz.org/debian-systs

Note: per default on ubuntu system, root task are done with sudo

This can be achieved by the following commands, as root or as privileged "sudo" user

# [sudo] echo "deb http://download.openvz.org/debian-systs etch openvz" >> /etc/apt/sources.list
# wget http://download.openvz.org/debian-systs/dso_archiv_signing_key.asc
# [sudo] apt-key add dso_archiv_signing_key.asc
# [sudo] apt-get update

Kernel installation

Note: In case you want to recompile the OpenVZ kernel yourself on Debian, see kernel build debian.

First, you need to choose what “flavor” of the kernel you want to install.

 # apt-get install <flavour>

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/menu.lst file:

[...]
  title           Debian GNU/Linux, kernel 2.6.18-ovz-028stab051.1-686
  root            (hd0,1)
  kernel          /vmlinuz-2.6.18-ovz-028stab051.1-686 root=/dev/sda5 ro vga=791
  initrd          /initrd.img-2.6.18-ovz-028stab051.1-686
  savedefault
[...]

Note: per default on debian/ubuntu, a 2.6.22 kernel will boot before a 2.6.18, please check manually the grub boot order. See man update-grub for more details

Rebooting into OpenVZ kernel

Warning: Before you restart your Server, keep in mind, that your system has all needed modules enabled; booting from your harddisk (e.g. hardware modules, raid system(s), lvm2 etc). May you need a INITRD (initramdisk) or compile needed kernel modules statically in.

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

Installing the user-level tools

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).

 # [sudo] apt-get install vzctl vzquota

Configuring

sysctl

There are 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.

Note: vzctl version from debian-systs, automate changing sysctl options for openvz

[...]

# On Hardware Node we generally need
# packet forwarding enabled and proxy arp disabled
net.ipv4.conf.default.forwarding=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

[...]

Note: You can make a symlink from /var/lib/vz to /vz as backward compability to Main OpenVZ

(Debian vz root directory is installed FHS-like to /var/lib/vz

 # [sudo] ln -s /var/lib/vz /vz

VE OS Templates

To install a VE, you need VE OS Template(s), precreated can be found here or create it : Debian , ubuntu and all about Templates

Note: Setup your prefered standard OS Template : edit the /etc/vz/vz.conf

Note: Debian Packages of a precreate Debian 4.0 can be fetch from Repository at http://download.openvz.org/debian-systs

 # [sudo] apt-get install vzctl-ostmpl-debian

Additial user tools

vzprocps: A set of utilities to provide system information (vzps and vztop)
vzdump: A utility to backup and restore VE.

Note: Debian Packages can be fetch from Repository at http://download.openvz.org/debian-systs

 # [sudo] apt-get install vzprocps vzdump

OpenVZ Virtuozzo Containers Wiki β