This is a script for quickly creating new Vservers for a Linux-Vserver patched system.

#!/usr/bin/perl
use strict;
use warnings;

# A script for quickly creating new Vservers for a Linux-Vserver system.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

# By JB Consulting Oy Ab / Jani Reinikainen [ jani (at) jbc (dot) fi ]
# Version 0.4.0 (10. November 2007). http://jbc.fi/


my $vserverpath = '/var/lib/vservers';
my $distrib     = 'gutsy';

if (!$ARGV[0]) {
 die("Need at least one argument (vserver name)! Usage:\n ./newvserver.pl [name] [IP]\n");
}

my $ip = '';

if ($ARGV[1]) {
 $ip = $ARGV[1];
}

# Check that a vserver with this name is not already running
my $output = `vserver-stat | grep $ARGV[0]\$`;

if ($output ne '') {


 print "Vserver with name $ARGV[0] already running! Stop vserver? [y/N] ";
 my $choice = ;
 chop($choice);
 if ($choice eq 'Y' || $choice eq 'y') {
  print "Attempting to stop vserver $ARGV[0].\n";
  `vserver $ARGV[0] stop`;
 } else {
  print "Not stopping vserver. Aborting.\n";
  exit(); 
 }
}

# Check if vserver path exists
if (-e "$vserverpath/$ARGV[0]") {
 print "$vserverpath/$ARGV[0] already exists! Move $vserverpath/$ARGV[0] to $vserverpath/$ARGV[0].old? [y/N] ";
 my $choice = ;
 chop($choice);

 if ($choice eq 'Y' || $choice eq 'y') {
  print "Attempting to move old vserver files out of the way.\n";
  `mv $vserverpath/$ARGV[0] $vserverpath/$ARGV[0].old`;

  if (-e "$vserverpath/$ARGV[0]") {
   print "Move seems to have failed. Aborting.\n";
   exit();
  }
 } else {
  print "Not moving old vserver files. Aborting '$choice'.\n";
  exit();
 }
}


# Check if configuration files with this name exist
if (-e "/etc/vservers/$ARGV[0]") {
 print "Configuration files exist in /etc/vservers/$ARGV[0]. Move to /etc/vservers/$ARGV[0].old? [y/N] ";
 my $choice = ;
 chop($choice);

 if ($choice eq 'Y' || $choice eq 'y') {
  print "Attempting to move old configuration files.\n";
  `mv /etc/vservers/$ARGV[0] /etc/vservers/$ARGV[0].old`;

  if (-e "/etc/vservers/$ARGV[0]") {
   print "Move seems to have failed. Aborting.\n";
   exit();
  }
 } else {
  print "Not moving old configuration files. Aborting.\n";
  exit();
 }
}

# Install base distribution
system("vserver $ARGV[0] build -n $ARGV[0] --hostname $ARGV[0] --interface eth0:$ip -m debootstrap -- -d $distrib");

# Symlink IP to hostname for quick reference
print "Symlinking $ip to $ARGV[0]\n";
chdir($vserverpath);
system("ln -s $ARGV[0]/ $ip");

# Generate hosts
system("echo '$ip\t$ARGV[0]' > $vserverpath/$ARGV[0]/etc/hosts");

# Generate sources.list for APT
system("echo 'deb http://fi.archive.ubuntu.com/ubuntu/ $distrib main restricted universe multiverse' > $vserverpath/$ARGV[0]/etc/apt/sources.list");
system("echo 'deb http://fi.archive.ubuntu.com/ubuntu/ $distrib-updates main restricted' >> $vserverpath/$ARGV[0]/etc/apt/sources.list");
system("echo 'deb http://fi.archive.ubuntu.com/ubuntu/ $distrib-backports main restricted universe multiverse' >> $vserverpath/$ARGV[0]/etc/apt/sources.list");
system("echo 'deb http://security.ubuntu.com/ubuntu $distrib-security main restricted' >> $vserverpath/$ARGV[0]/etc/apt/sources.list");

# Install language pack to avoid errors about locales
chroot("$vserverpath/$ARGV[0]");
system("apt-get update; apt-get install -y --force-yes language-pack-en-base");

# Remove crippled shell
system("rm /bin/sh");
system("ln -s /bin/bash /bin/sh");

# Start vserver while we're at it?
print "All done! Do you wish to start the vserver now? [Y/n] ";
my $choice = ;
chop($choice);

if ($choice ne 'N' || $choice ne 'n') {
 print "Attempting to start vserver $ARGV[0].\n";
 `vserver $ARGV[0] start`;
}

Some almost always useless stuff gets installed as well, so I usually do this inside the newly created Vserver (example is for Ubuntu Gutsy, i.e. 7.10):