Hi, On Wed, Jun 04, 2008 at 01:16:31AM +0200, Lars Marowsky-Bree wrote: > On 2008-06-03T16:35:22, "Hildebrand, Nils, 232" <[EMAIL PROTECTED]> wrote: > > > > - [Quality not important for hardware?] > > I think the truth is somewhere in between. If you have a cluster it is > > not that important if a node goes down (depending on how available your > > services have to be). > > Right, but telling customers to save on hardware because they are > getting clustering is, uhm, not something I'd advocate ;-)
Indeed. Clusters are not a replacement for good hardware. A perfect cluster is one which is never exercised (unless when testing) ;-) [snip] > > > - [time is important - but only for logs] > > Why is there a heartbeat-message "time has jumped back - compensating"? > > That doesn't track whether time is set correctly, but whether the system > time as reported is monotonously increasing. And if it is not, it is > compensated for. > > That can happen when the clock is adjusted abruptly, ie it is a possible > side effect of running ntpdate via cron too. Not all applications can > compensate this, some will exhibit rather strange behaviour because they > are more trusting than our rather paranoid libraries ;-) > > xntpd avoids this by smoothing all jumps and only making minimal > adjustments. The right combination is to use ntpdate once at system boot > and then run xntpd (like the xntp init script does.) Some virtual environments are notoriously bad at keeping time (vmware for example). I think that sometimes ntp can't prevent clock from jigger. Thanks, Dejan _______________________________________________ Linux-HA mailing list Linux-HA@lists.linux-ha.org http://lists.linux-ha.org/mailman/listinfo/linux-ha See also: http://linux-ha.org/ReportingProblems
