[ale] Time jumping forward on RHEL6.3

Wed Nov 21 08:43:07 EST 2012

I did use ntpdate to set the time when I first saw this last week.  The question is NOT "How to do I get my time to the right value?" - I already know about both the date and the ntpdate commands.

The question IS "What is causing my 'system' time to jump ahead"?   As noted in prior posts this has occurred both with ntpd running and not running and is NOT affecting the hardware clock.

Yesterday I found another server in my environment is running RHEL6.3 and same version of ntpd which is not exhibiting this problem.   What I don't have is another Dell PowerEdge R620 so I'm beginning to suspect this may be an issue with the hardware but I'm at a loss to explain what in the hardware would be making the 'system' clock but not the 'hardware' clock jump like this.

Also as mentioned yesterday I checked system time on all of our Linux servers and only the two I originally questioned are off.

On checking this morning I see the time on these two is still off by 20 hours so it hasn't gotten any worse since I last looked at it yesterday.   However, since it seemed to be OK through the past weekend and half the day on Monday I'm not sure what would be causing this.   Research on the internet has not turned up similar problems with Linux or ntp time nor any issue with R620s that would seem to be the same.

Are any of you running R620s?   If so is your time correct and what distro/version of Linux are you running?

-----Original Message-----
From: ale-bounces at ale.org [mailto:ale-bounces at ale.org] On Behalf Of Erik Mathis
Sent: Tuesday, November 20, 2012 6:19 PM
To: Atlanta Linux Enthusiasts
Subject: Re: [ale] Time jumping forward on RHEL6.3

I typically fix these issues with ntpdate -b <server>

If the skew in time is too great, ntp wont try and fix. -b overrides this.

-Erik-

On Tue, Nov 20, 2012 at 2:03 PM, Lightner, Jeff <JLightner at water.com> wrote:
> I specifically mentioned ntp in my post.   The issue occurred WITH ntp running last week and yesterday and apparently it was the issue occurring yesterday that caused ntp to abort because the time difference was too great which as I noted is likely the effect of having added the -x option (that is it didn't abort last week when I saw the time off).
>
> Since the time has continued to move ahead with ntp not running I don't believe this is an ntp issue.
>
> I don't believe it is a battery issue because as I noted I rebooted the servers both last week and yesterday morning to verify the time it got after reboot is correct.
>
> Since the system time is only set from hardware on boot, even if the hardware clock were off I wouldn't expect it to modify system time while the OS is running.   Also hwclock command has reported the correct time every time I've checked it so that wouldn't be the problem.   That is to say it isn't the hardware clock time that is jumping but rather the OS time as reported by the "date" command.
>
>
>
>
>
> -----Original Message-----
> From: ale-bounces at ale.org [mailto:ale-bounces at ale.org] On Behalf Of 
> simontek at gmail.com
> Sent: Tuesday, November 20, 2012 1:30 PM
> To: Atlanta Linux Enthusiasts
> Subject: Re: [ale] Time jumping forward on RHEL6.3
>
> Are you using ntp? If not, why not? Also could the battery be shot on the mobo?
> Sent via BlackBerry from T-Mobile
>
> -----Original Message-----
> From: Brian MacLeod <nym.bnm at gmail.com>
> Sender: ale-bounces at ale.org
> Date: Tue, 20 Nov 2012 13:24:37
> To: <ale at ale.org>
> Reply-To: Atlanta Linux Enthusiasts <ale at ale.org>
> Subject: Re: [ale] Time jumping forward on RHEL6.3
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA256
>
> On 11/20/12 11:26 AM, Lightner, Jeff wrote:
>>
>> A ticket has been opened with RedHat support but I?m wondering if 
>> anyone has seen something like this and has any ideas what might be 
>> causing it or how to prevent it.  We?ll be running cluster software 
>> on these two nodes so having time synchronizes is especially important.
>>
>
>
> I have not seen any indication of a time jump on any of our RHEL6 cluster nodes or VMs in the HPC environment here at GT. The last time I saw anything like that was on some older Sun equipment where the LOM had a known bug that after 536 days of continuous operation would wrap a counter and time would jump.  It was a DB server.  Yeah, fun.
>
> Brian
>
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG/MacGPG2 v2.0.18 (Darwin)
> Comment: Using GnuPG with undefined - http://www.enigmail.net/
>
> iQE4BAEBCAAiBQJQq8rlGxhoa3A6Ly9rZXlzZXJ2ZXIudWJ1bnR1LmNvbQAKCRD5
> XCJY/q4Y6DYsCACLLtxj/LB5unH7q73348WdSP2hZ210+SLN8/BUle+IfXIyvX/B
> KGqipTZB+qJKS+XSUhfzxTNj/b62hTJIV/MQVWJK6dnHJ6BoDuUjj/w3lQX41kJu
> EeJir959AvdbjBKS0AyZ3Iiun184Gf2dlhdEsLstW8bpVtXj9sf7oiJ6wDBqVOyU
> aQN2dwLJPfYbRU2HHW4dseVvk3JlVwtXytJ/ZIcG6ZKbF5my3t7pfmn1niD0P9Sb
> 8Krlw3+w5rzUVw/TE5WuSogMOMlUpgLklGNkrBKE8vlqR2Ydr64GY0mpw24Qi3Mh
> dTUHkHq/+YkiS9403NleVulKz+VVQq5uKDti
> =8llY
> -----END PGP SIGNATURE-----
> _______________________________________________
> Ale mailing list
> Ale at ale.org
> http://mail.ale.org/mailman/listinfo/ale
> See JOBS, ANNOUNCE and SCHOOLS lists at 
> http://mail.ale.org/mailman/listinfo
>
> _______________________________________________
> Ale mailing list
> Ale at ale.org
> http://mail.ale.org/mailman/listinfo/ale
> See JOBS, ANNOUNCE and SCHOOLS lists at 
> http://mail.ale.org/mailman/listinfo
>
>
>
>
> Athena(r), Created for the Cause(tm)
> Making a Difference in the Fight Against Breast Cancer
>
> ---------------------------------
> CONFIDENTIALITY NOTICE: This e-mail may contain privileged or confidential information and is for the sole use of the intended recipient(s). If you are not the intended recipient, any disclosure, copying, distribution, or use of the contents of this information is prohibited and may be unlawful. If you have received this electronic transmission in error, please reply immediately to the sender that you have received the message in error, and delete it. Thank you.
> ----------------------------------
>
>
> _______________________________________________
> Ale mailing list
> Ale at ale.org
> http://mail.ale.org/mailman/listinfo/ale
> See JOBS, ANNOUNCE and SCHOOLS lists at 
> http://mail.ale.org/mailman/listinfo

_______________________________________________
Ale mailing list
Ale at ale.org
http://mail.ale.org/mailman/listinfo/ale
See JOBS, ANNOUNCE and SCHOOLS lists at
http://mail.ale.org/mailman/listinfo