DHCP Failover questions

[Jason Frisvold]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Nov 13, 2009, at 2:54 PM, sthaug at nethelp.no wrote:
> No. The failover peer "foo" name needs to be the same on primary and
> secondary, and also needs to be the same as the failover peer "foo"
> inside the pool declaration.
> 
> Note that you can have multiple failover associations. So for instance
> server A at a main office can have a failover association (e.g. "AB")
> with server B at one branch office, and another failover association
> (e.g. "AC") with server C at a different branch office. Server B would
> have failover peer "AB" inside the pool declaration(s) and also in the
> failover declaration, while server C would have failover peer "AC"
> inside the pool declaration(s) and in the failover declaration.
> 
> When the servers in a failover pair are communicating, you should expect
> to see messages along the following lines in the logs:
> 
> Restarting one server, messages on this server:
> 
> Nov 13 06:56:10 dhcp2 dhcpd: failover peer dhcp1-dhcp2: I move from normal to startup
> Nov 13 06:56:11 dhcp2 dhcpd: failover peer dhcp1-dhcp2: peer moves from normal to communications-interrupted
> Nov 13 06:56:11 dhcp2 dhcpd: failover peer dhcp1-dhcp2: I move from startup to normal
> Nov 13 06:56:11 dhcp2 dhcpd: failover peer dhcp1-dhcp2: peer moves from communications-interrupted to normal

Interestingly enough, we do see these messages..

> and on the other server in the failover pair (you *do* have them NTP
> synchronized, I hope):

Of course.  :)

> For the DHCPDISCOVER messages you should expect to see them in the logs
> on both servers, with one of the servers saying "load balance to ...",
> e.g.:
> 
> Nov 13 20:49:06 dhcp1 dhcpd: DHCPDISCOVER from 00:1c:df:3f:e6:ca via 81.191.80.1
> 
> Nov 13 20:49:06 dhcp2 dhcpd: DHCPDISCOVER from 00:1c:df:3f:e6:ca via 81.191.80.1: load balance to peer dhcp1-dhcp2

Aha ..  this is what we're not seeing.  I will modify the configuration accordingly during our maintenance window and get this running properly.

> Steinar Haug, Nethelp consulting, sthaug at nethelp.no

- ---------------------------
Jason Frisvold
Network Engineer
frisvolj at lafayette.edu
- ---------------------------
"What I cannot create, I do not understand"
   - Richard Feynman      

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)

iEYEARECAAYFAkr91Q8ACgkQO80o6DJ8UvmCbwCeI4CZcvPYkCr2Fwq3MugDg/xv
D6IAnirXI9EKIFcr9161vNndXgFyhcFw
=qiJv
-----END PGP SIGNATURE-----