I personally have become discouraged about actual client compliance with the redundant DNS philosophy. I've seen too many cases where a primary goes down, secondary has the right info, but clients can't see the site (or whatever). I haven't done any analysis to see what servers are at fault but it's typically in a MS-only office where those problems crop up.
On Mon, 9 Jun 2003, Dave Belfer-Shevett wrote: > > Hi all - good question for BBLISA folks. > > We have a large cluster of machiens that have 3 DNS servers available to > them. (sdm[123]). We run applications on the cluster that are 'startup & > run' type of services. > > The problem is that these applications seem to start, check > /etc/resolv.conf, pick a nameserver, and stick to it. If the nameserver > it attaches to (the first one on the list probably) goes down (either > named dying or the machine rebooting), all the applications wedge with > failed lookups. > > We need a stronger failover mechanism for these clusters - how do folks > handle this sort of situation? > > One thing that has been proposed is using a localized 'caching only' named > configuration on each of the servers, with a list of 'upstream' servers > (sdm[123]) to consult if the cache doesn't have the answer. > > I've thought about round-robin DNS for the nameservers - but does > libresolv actually handle that appropriately? Eg, if I call libresolv to > do a nametoaddress lookup, and we say 'use sdm for resolution', will it > keep poking whatever IP 'sdm' is for the answer? > > How do folks handle fault-tolerant nameservice inside high availability > clusters? > > (btw - these are all Sun machines, running Solaris 7 or higher) > > -- > ------------------.--------. > Dave Belfer-Shevett\ KB1FWR \ > www.homeport.org >--------`------------------------------------ > [EMAIL PROTECTED] / "Life imitates art far more than art \ > ------------------< imitates life." (Oscar Wilde - | > | www.chiasmus.com) | > \______________________________________________/ > > > --- > Send mail for the `bblisa' mailing list to [EMAIL PROTECTED]'. > Mail administrative requests to [EMAIL PROTECTED]'. > --- Send mail for the `bblisa' mailing list to [EMAIL PROTECTED]'. Mail administrative requests to [EMAIL PROTECTED]'.
