Archive for September, 2009

Adjusting RAM for an OpenVZ VPS

Sunday, September 6th, 2009  1 Comment

Here are commands to help adjust the RAM for an OpenVZ VPS:

64MB Guaranteed, 128MB Burstable

cid=1000
vzctl set ${cid} --vmguarpages $((64 * 64)) --save
vzctl set ${cid} --privvmpages $((64 * 128)) --save

256MB Guaranteed, 512MB Burstable

cid=1000
vzctl set ${cid} --vmguarpages $((256 * 256)) --save
vzctl set ${cid} --privvmpages $((256 * 512)) --save

512MB Guaranteed, 1024MB Burstable

cid=1000
vzctl set ${cid} --vmguarpages $((512 * 512)) --save
vzctl set ${cid} --privvmpages $((512 * 1024)) --save

1024MB Guaranteed, 2048MB Burstable

cid=1000
vzctl set ${cid} --vmguarpages $((1024 * 1024)) --save
vzctl set ${cid} --privvmpages $((1024 * 2048)) --save

Adding NFS support to an OpenVZ VPS

Sunday, September 6th, 2009  No Comment

I still use a lot of NFS connections on my equipment and when I create OpenVZ VPS systems I need them to have access to NFS. Here are the steps I use:

From the Host Node (HN):

modprobe nfs
vzctl set 101 --features "nfs:on" --save

From the VPS:

yum -y install nfs-utils nfs-utils-lib
chkconfig --levels 345 portmap on
/etc/init.d/portmap start

Setting up an OpenVZ VPS DNS Server in CentOS 5.3

Sunday, September 6th, 2009  No Comment

Here is my quick-and dirty way to build DNS servers using OpenVZ, CentOS and Bind/Named. This assumes you are creating a new server via OpenVZ. Although Bind is easy to admin with the configuration files recently I have found it is easier to simply admin the zones with Webmin. This setup will create the VPS, install Bind and install Webmin.

Create the VPS:

cid=1161
cd /vz/template/cache/
wget http://download.openvz.org/template/precreated/centos-5-x86_64.tar.gz
vzctl create ${cid} --ostemplate centos-5-x86_64 --config vps.basic
vzctl set ${cid} --hostname [HOSTNAMEHERE] --save
vzctl set ${cid} --ipadd [IP] --save
vzctl set ${cid} --nameserver [IP] --save
vzctl start ${cid}
vzctl exec ${cid} passwd
vzctl enter ${cid}

From inside the VPS I install bind and webmin

yum -y install bind bind-chroot bind-libs bind-utils caching-nameserver
cd /root
wget http://prdownloads.sourceforge.net/webadmin/webmin-1.480-1.noarch.rpm
rpm -Uvh webmin-1.480-1.noarch.rpm

Now I simply visit webmin’s panel and tap in any new zones (or copy over our zones from another box).

OpenVZ and virtual serving makes this time-consuming task of bringing new boxes up a simple task!

Installing OpenVZ in CentOS 5.3 (64bit)

Saturday, September 5th, 2009  No Comment

There are a few tutorials out there on installing OpenVZ in CentOS 5.3. Here are the steps I use to install OpenVZ on a brand new installation of CentOS 5.3:

Note: this tutorial / walkthrough is for use 64 bit only

  1. Update the box via yum
  2. Install the OpenVZ Repository and grab the GPG key
  3. Install OpenVZ
  4. Install OpenVZ Controller and Quota system
  5. Configure the local system for the OpenVZ kernel
  6. Update OpenVZ’s ARP Settings
  7. Disable SELINUX
  8. Reboot
yum -y update
cd /etc/yum.repos.d
wget http://download.openvz.org/openvz.repo
rpm --import http://download.openvz.org/RPM-GPG-Key-OpenVZ
yum -y install ovzkernel.x86_64
yum -y install vzctl.x86_64 vzquota.x86_64

Now; we need to configure the sysctl.conf file for OpenVZ

perl -pi -e 's/net\.ipv4\.ip_forward = 0/net\.ipv4\.ip_forward = 1/' /etc/sysctl.conf
perl -pi -e 's/kernel\.sysrq = 0/kernel\.sysrq = 1/' /etc/sysctl.conf
echo -e "\n\nnet.ipv4.conf.default.proxy_arp = 0\nnet.ipv4.conf.all.rp_filter = 1\nnet.ipv4.conf.default.send_redirects = 1\nnet.ipv4.conf.all.send_redirects = 0\nnet.ipv4.icmp_echo_ignore_broadcasts=1\nnet.ipv4.conf.default.forwarding=1\nkernel.ve_allow_kthreads=1\n" >> /etc/sysctl.conf
perl -pi -e 's/NEIGHBOUR_DEVS=detect/NEIGHBOUR_DEVS=all/' /etc/vz/vz.conf

Disable SELINUX

vi /etc/sysconfig/selinux

Reboot the machine

reboot