12.02.2013, 20:50, "Mauricio Tavares" <raubvogel@xxxxxxxxx>: > On Thu, Jan 3, 2013 at 9:01 PM, Nico Kadel-Garcia <nkadel@xxxxxxxxx> wrote: > >> On Jan 2, 2013, at 19:27, "James B. Byrne" <byrnejb@xxxxxxxxxxxxx> wrote: >>> I do that as well. However, I run one on each host just to serve its >>> own guests and configure the host to run off our central ntp server. >> Unfortunately, before our upstream vendor's OS release 6, ntp.conf >> listed several loopback addresses by default. These allowed a confused >> ntpd to basically marry its siblings and eventually crossbreed itself >> to a fairly stange state. But it will report ntpd as active, which is >> why the Nagios check "chek_ntp_)time" actually compares the time to a >> known good upstream NTP service. > > Dumb question: why not use the vm host's clock instead? I am > coming from libvirt but I would assume (bad idea I know) that if > libvirt can see the host's clock in the client, so can kvm. If that is > the case, something like > > hwclock -s -u > > should keep them in sync. I wrote a little cron job (see > http://unixwars.blogspot.com/2013/01/restoring-time-on-sleeping-linux-vms.html) > to compare the client time with the host. If the drift is large > enough, sync them back. The reason for the cron job is so it works > after client wakes up from a slumber. Just throwing an idea out there. > > On a side note, yes I did also write another script using ntpq and > ntpdate to adjust time using ntp. I guess each solution has its > merits. =) > >>>>> 4. On each guest have a cron job that checks for ntpd at regular >>>>> intervals which reports failures and restarts the time service as >>>>> necessary. We use: >>>>> JOBNAME="Check ntpd status and restart if required" ; \ >>>>> ntpstat > /dev/null && \ >>>>> if [[ $? -gt 0 ]]; then /sbin/service ntpd start; fi >>>> Why not configure the ntpd daemon and stick with that? >>>> It does update on its own [1]. And ntpstat prints out the interval, >>>> which matches the one mentioned at [1]. >>>> I don't believe the ntpstat script/job is necessary (I've never had to >>>> do more than set ntpd to run after configuring the servers it should >>>> poll). >> See above. The 'check_ntp_time' tool is much more flexible and complete. >> itten does work. It's part of the "nagios-plugions-ntp" package, >> available from EPEL and RPMforge. >> _______________________________________________ >> CentOS-virt mailing list >> CentOS-virt@xxxxxxxxxx >> http://lists.centos.org/mailman/listinfo/centos-virt > > _______________________________________________ > CentOS-virt mailing list > CentOS-virt@xxxxxxxxxx > http://lists.centos.org/mailman/listinfo/centos-virt Hi. To get the same at all WM. I installed and configured ntp-server. -- Трудно жить ничего не делая, но мы привыкли бороться с трудностями. _______________________________________________ CentOS-virt mailing list CentOS-virt@xxxxxxxxxx http://lists.centos.org/mailman/listinfo/centos-virt