[CentOS] ISC DHCP failover

Wed Sep 23 20:16:33 UTC 2015
m.roth at 5-cent.us <m.roth at 5-cent.us>

Chris Adams wrote:
> Anybody have any experience with setting up dhcpd in failover mode
> between two servers?  I set this up on a couple of servers, and it seems
> to be working, but I don't think it is working "right".  It appears both
> servers are replying to all requests (which for renewals works okay
> because they both give the same address, but new requests get two
> different responses).  I thought that only one server would reply to a
> particular request.
In our /etc/dhcp/dhcpd.conf, we have a stanza

failover peer "dhcp" {
        address <primary IP address;
        port 519;
        peer address <failovee peer IP address>;
        peer port 520;
        max-response-delay 300;
        max-unacked-updates 10;
        mclt 600;
        split 128;
        load balance max seconds 3;

Hope that helps.