How to add a new IP range to Citrix XenServer?

When running out of current assigned IP ranges, you will need to add a new IP range to Citrix XenServer before can assigning it to specific VMs. This tutorial contains step-by-step guide on this work. The following work will be done in the main server which hosts Citrix XenServer.

• When requesting additional IPs you should specifically request that a full network block be assigned. Regardless of what size you are assigned, you will need to use 3 IP addresses for administrative purposes (1 as a network address, 1 as a broadcast address and 1 as the “default gateway”).  For example:
  • The requested IP block is XXX.XXX.XXX.112/29
  • Usable IP Range – XXX.XXX.XXX.114 – XXX.XXX.XXX.118
  • Gateway – XXX.XXX.XXX.113
  • Netmask – 255.255.255.248
• Create a new network interface for new IP range:

  vi /etc/sysconfig/network-scripts/ifcfg-newiprange

• Remember to set the device information in the new network interface to dummy0. Sample configuration is as follows (the YOUR_FIRST_UNUSED_IP IP in the above example is XXX.XXX.XXX.114):

  XEMANAGED=yes
  DEVICE=dummy0
  ONBOOT=no
  NOZEROCONF=yes
  TYPE=Ethernet
  BOOTPROTO=none
  NETMASK=XXX.XXX.XXX.XXX
  IPADDR=YOUR_FIRST_UNUSED_IP
  GATEWAY=YOUR_GATEWAY_IP
  MTU=1500
  DNS1=YOUR_DNS_INFORMATION
  DNS2=8.8.8.8
  DOMAIN='YOUR_DOMAIN_AS_CURRENT_XEN_DOMAIN'

• Setting up the new network interface:

  ifup newiprange

• Try pinging your first assigned IP in

  YOUR_FIRST_UNUSED_IP

• Next, you will need to add the remaining unsed IPs in your new IP range to the route:

  ip route add XXX.XXX.XXX.115 dev xenbr0
  ip route add XXX.XXX.XXX.116 dev xenbr0
  ip route add XXX.XXX.XXX.117 dev xenbr0
  ip route add XXX.XXX.XXX.118 dev xenbr0

• Finally, you need to add the above commands to the end of the /etc/rc.local file so that the routes are established any time you reboot the server.
• That’s all! You can now using the new IP range in your guest VMs.