CentOS is one of the most popular free and open source server operating systems. OpenVZ is a popular open source system for creating virtual private servers. Combine the two together, and you have a low-cost yet powerful VPS system. The following is a brief installation guide to get OpenVZ running on CentOS.
Add the OpenVZ repository to Yum:
cd /etc/yum.repos.d wget http://download.openvz.org/openvz.repo rpm –import http://download.openvz.org/RPM-GPG-Key-OpenVZ
Edit openvz.repo and disable the [openvz-kernel-rhel5] repository (enabled=0) and enable the [openvz-kernel-rhel6] repository.
Install the OpenVZ kernel:
Search using:
yum search vzkernel
Choose the kernel you want and install:
yum install vzkernel
(This should automatically update Grub to your new kernel. If not, you may need to manually edit your grub configuration).
Install OpenVZ user tools:
yum install vzctl vzquota
Edit /etc/sysctl.conf and ensure you have these settings:
net.ipv4.ip_forward = 1 net.ipv4.conf.default.proxy_arp = 0 net.ipv4.conf.all.rp_filter = 1 kernel.sysrq = 1 net.ipv4.conf.default.send_redirects = 1 net.ipv4.conf.all.send_redirects = 0 net.ipv4.icmp_echo_ignore_broadcasts=1 net.ipv4.conf.default.forwarding=1
If your IP addresses for your virtual machines will be on a different subnet than your host machine, you need to make sure you have this in /etc/vz/vz.conf:
NEIGHBOUR_DEVS=all
Disable SELinux bye editing /etc/sysconfig/selinux:
# enforcing – SELinux security policy is enforced. # permissive – SELinux prints warnings instead of enforcing. # disabled – No SELinux policy is loaded. SELINUX=disabled
Reboot
You should now have a working OpenVZ installation. You should then test it to verify that the kernel is running and that you are able to create containers.