Home

Welcome to the build_isc_dhcp wiki!

ONA Configuration

Failover

DHCP failover is built into the core of ONA. To enable DHCP failover for a DHCP pool you must do the following:

• In the admin menu Menu->Admin->Manage DHCP failover groups you must select two existing hosts to be part of the failover pair.
• Select your desired Split value. The default will put all IPs from a /24 bit subnet on the primary host. Another common value is 128 to split evenly between both primary and secondary hosts.
• Adjust any other values as needed but usually the defaults are sufficient.
• Now either add a DHCP pool or edit an existing one and select this failover group for the pool.
• Remember that a subnet should have at least a default gateway DHCP option allocated for it to show up on the server. The subnet/pool will automatically be added to the hosts defined in the failover group.
• That should be it. Also ensure any firewall rules are updated so that failover traffic will flow between the peers on ports 647/847.

Good info on DHCP failover configuration: http://canonical.wordpress.com/2009/11/22/dhcp-failover-with-isc-dhcp/

That link is broken, try this: https://kb.isc.org/article/AA-00502/0/A-Basic-Guide-to-Configuring-DHCP-Failover.html