FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > CentOS > CentOS

 
 
LinkBack Thread Tools
 
Old 11-22-2009, 05:02 AM
Brian Mathis
 
Default system time automatically fowards in time and then comes back to normal

On Sun, Nov 22, 2009 at 12:19 AM, ankush grover <ankushcentos@gmail.com> wrote:
> Hi friends,
>
> I am running Nagios 2.7-1 on Centos 5.0 32-bit hosted on Vmware ESX
> 4.0. The issue I am seeing on the server is sometimes nagios is
> showing the below messages in /var/log/messages and as the system time
> gets changed some false alarms gets generated. I searched it on the
> google but I am not able to find the correct solution. I even posted
> on the nagios forum and they asked me to see elsewhere why the server
> shitfs so much before looking at nagios.
>
>
> Nov 21 20:37:12 linuxmonitoring nagios: Warning: A system time change
> of 4398 seconds (forwards in time) has been detected. *Compensating...
> Nov 21 19:23:54 linuxmonitoring nagios: Warning: A system time change
> of 4398 seconds (backwards in time) has been detected. *Compensating..
>
>
> Earlier this server was syncing time through ntp daemon and below is
> the ntp.conf file. Now I have set a cronjob which sync the time with
> the ntp server every 5 minutes but still the problem persist.
>
> ntp.conf file
>
>
> restrict default ignore
> restrict 127.0.0.1
> driftfile /var/lib/ntp/drift
> broadcastdelay 0.008
> #authenticate yes
> keys /etc/ntp/keys
> restrict 172.16.6.3 nomodify notrap noquery
> server 172.16.6.3
> restrict 172.16.6.2 nomodify notrap noquery
> server 172.16.6.2
>
> Please see the output of hwclock and date at the same time.
> hwclock
> Sat 21 Nov 2009 08:19:02 PM IST *-0.496922 seconds
>
> date
> Sat Nov 21 20:19:55 IST 2009
>
> Please advice what I need to do to fix this error.
>
> Regards
> Ankush


Because you are using VMware you must become very familiar with how
timekeeping works on computer systems. VMware has some helpful guides
on this:
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId= 1006427
http://www.vmware.com/pdf/vmware_timekeeping.pdf
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-22-2009, 02:30 PM
Akemi Yagi
 
Default system time automatically fowards in time and then comes back to normal

On Sun, Nov 22, 2009 at 7:08 AM, nate <centos@linuxpowered.net> wrote:
> ankush grover wrote:
>
>> Earlier this server was syncing time through ntp daemon and below is
>> the ntp.conf file. Now I have set a cronjob which sync the time with
>
> Best not to run NTP inside a ESX VM. I've never gotten NTP to sync
> inside of VMware outside of a kernel with VMI enabled (no versions
> of RHEL support VMI at this time as far as I know).

As quoted by Brian earlier in this thread, the VMware knowledge base
offers their "best practices for Linux guests" in :

http://kb.vmware.com/kb/1006427

for VMware products including ESX and ESXi. According to their
current recommendations, " In all cases use NTP instead of VMware
Tools periodic time synchronization."

The above KB articles gets updated from time to time, so it is a good
idea to check it back occasionally.

Akemi
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-22-2009, 08:06 PM
Akemi Yagi
 
Default system time automatically fowards in time and then comes back to normal

On Sun, Nov 22, 2009 at 12:19 PM, Clint Dilks <clintd@scms.waikato.ac.nz> wrote:

> The OP should also reference this document
> http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId= 1006427

This is the 3rd time that KB article was quoted in this thread... :-D

Akemi
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 

Thread Tools




All times are GMT. The time now is 09:29 AM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org