On Oct 2, 2012, at 3:40 PM, da...@lang.hm wrote: > On Tue, 2 Oct 2012, Aaron Hall wrote: > >> We're considering ways to provide redundant DHCP to maintain service >> should our (physical) server go down suddenly. We're using isc-dhcpd on >> RHEL. One server handles all of campus, and it's not breaking a sweat. >> >> * Should the master server go down, we'd sanity-check the config on the >> backup, and turn on dhcpd. This could be a manual or automatic >> process. > > > as for warrying about a master server dieing in the middle of a copy, write > the copied file to a new filename and rename it over the old version. rsync > does this by default, so as long as you could tolorate some files getting > copied but not others as a worst case, rsync will prevent you from having a > partially copied file. >
One thing I've done in the past is to use static reservations, being served actively by multiple servers, and copying the master config & files to shared storage and then out to slave nodes every few minutes. * we copied from shared storage to local, just in case we had a power failure, etc. * we linted the file via the ISC script before we restarted, just to make sure it was a valid config. This wasn't on a campus w/ a large number of dynamic entities, but if you do have that, and you don't have a full registration system, then you can just let dynamic folks use 2 different pools. We were able to avoid *ANY* fancy HA systems, or failover, or any kind of trouble, even if we lost any server. These days we'd probably do it with puppet, or the like, but... overlapping DHCP servers with static reservations work very nicely. _______________________________________________ Tech mailing list Tech@lists.lopsa.org https://lists.lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
