Forum Discussion
swo0sh_gt_13163
Altostratus
AltostratusNTP time difference between Active / Standby appliance
Hello Folks,
It has been quite sometime when I post a question on DevCentral. So here we go, I have 2 F5 A/S appliances. Both are pointing to 2 NTP servers as 10.13.1.11 and 10.13.1.12. NTP traffic is passing through other than Management Interface so far.
What has been observed is, Active appliance is showing correct time as per the NTP server, however the standby appliance is showing 3 minutes of difference compare to the Active appliance. Even you sync the time manually, it slowly experience delay, and time difference start getting increased between both of the appliances.
Following is the result of the NTPQ -PN from Active and standby.
[root@Company_F5-3900U1:Active:In Sync] config ntpq -np
remote refid st t when poll reach delay offset jitter
==============================================================================
10.13.1.12 10.13.1.11 2 u 19 64 377 2.077 -43725. 11.051
10.13.1.11 .LOCL. 1 u 59 64
[root@Company_F5-3900U2:Standby:In Sync] config ntpq -pn
remote refid st t when poll reach delay offset jitter
==============================================================================
10.13.1.12 10.13.1.11 2 u 18 64 377 1.947 -222609 33.485
10.13.1.11 .LOCL. 1 u 21 64 377 1.953 -222588 28.426
If you see the Offset value on Standby appliance, that justifies the fact why there is a time difference between Active and Standby unit. The NTP servers are reachable via a DMZ interface i.e. 1.1. Both of the appliances have same configured of interfaces along with the media settings.
Following is the interface property of both of the appliances, which is exactly same.
root@(Company_F5-3900U2)(cfg-sync In Sync)(Standby)(/Common)(tmos) list net interface 1.1
net interface 1.1 {
if-index 80
mac-address 00:01:d7:e6:6d:44
media-active 1000T-FD
media-max 1000T-FD
mtu 1800
}
Any help?
Darshan
swo0sh_gt_13163I need to check this with customer. I will rectify this and let you know.
Thanks for all the help so far.
Cheers! Darsham
- swo0sh_gt_13163
Hey Nitass,
I got the result of the given command, following is the result for the same.
ntpq> as ind assID status conf reach auth condition last_event cnt =========================================================== 1 26404 9014 yes yes none reject reachable 1 2 26405 9014 yes yes none reject reachable 1 ntpq> rv 26404 assID=26404 status=9014 reach, conf, 1 event, event_reach, srcadr=deddc02.company.com, srcport=123, dstadr=192.168.10.87, dstport=123, leap=00, stratum=2, precision=-6, rootdelay=31.250, rootdispersion=10777.222, refid=10.13.1.11, reach=377, unreach=0, hmode=3, pmode=4, hpoll=6, ppoll=6, flash=400 peer_dist, keyid=0, ttl=0, offset=-254714.454, delay=2.979, dispersion=16.512, jitter=31.733, reftime=d8e6dec3.e036bc54 Sun, Apr 26 2015 7:49:23.875, org=d8e6df43.8c3eed7b Sun, Apr 26 2015 7:51:31.547, rec=d8e6e042.438701cb Sun, Apr 26 2015 7:55:46.263, xmt=d8e6e042.42c3c834 Sun, Apr 26 2015 7:55:46.260, filtdelay= 2.98 1.91 1.95 1.96 2.92 2.77 2.92 2.48, filtoffset= -254714 -254713 -254704 -254690 -254688 -254684 -254668 -254663, filtdisp= 15.63 16.62 17.59 18.57 19.56 20.50 21.45 22.41 ntpq> ntpq> ntpq> ntpq> ntpq> ntpq> rv 26405 assID=26405 status=9014 reach, conf, 1 event, event_reach, srcadr=deddc01.company.com, srcport=123, dstadr=192.168.10.87, dstport=123, leap=00, stratum=1, precision=-6, rootdelay=0.000, rootdispersion=10720.551, refid=LOCL, reach=377, unreach=0, hmode=3, pmode=4, hpoll=6, ppoll=6, flash=400 peer_dist, keyid=0, ttl=0, offset=-254702.557, delay=1.923, dispersion=16.489, jitter=22.221, reftime=d8e5f16b.43e76c8b Sat, Apr 25 2015 14:56:43.265, org=d8e6df55.88000000 Sun, Apr 26 2015 7:51:49.531, rec=d8e6e054.3c19d01d Sun, Apr 26 2015 7:56:04.234, xmt=d8e6e054.3b9bc63b Sun, Apr 26 2015 7:56:04.232, filtdelay= 1.92 1.97 1.92 1.93 1.93 1.91 1.92 1.97, filtoffset= -254702 -254704 -254698 -254691 -254676 -254675 -254672 -254671, filtdisp= 15.63 16.59 17.53 18.49 19.48 20.44 21.43 22.41 - nitass
Employee
I got the result of the given command
can you try "ntpdate -u 10.13.1.11"?
How to debug ntp issues?
https://rags.wordpress.com/2011/10/17/how-to-debug-ntp-issues/if it does not help, may you try this?
tmsh modify sys ntp include 'tos maxdist 16'Exadata -- Ntp Problem, actually a Windows Server problem
http://ermanarslan.blogspot.sg/2014/06/exadata-ntp-problem-actually-windows.html - swo0sh_gt_13163
Thanks Nitass,
I am going through the given articles now. By the way did you observe that the given result of
showsntpq> as
asreject
.conditionDoes it indicate anything? Thanks for your help so far.
Much appreciated.
Darshan
- nitassdispersion is high similar to the articles.
- swo0sh_gt_13163
Yea, also
showsFlash
for both of the peers. So now as you've mentioned, I am going to update the400
and NTP restart to see if that is working.tos maxdist 16I will update the thread after confirming the fact.
Thanks again Nitass!
- swo0sh_gt_13163
It seems the Windows server, which is configured as an NTP server on F5 is the culprit. After updating the timeout threshold to 16 (i.e. tos maxdist 16) it has improved the Offset. Now it seems as following.
[root@CompanyF5-3900U2:Standby:Changes Pending] config ntpq -pn remote refid st t when poll reach delay offset jitter ============================================================================== *10.13.1.12 10.13.1.11 2 u 4 64 1 0.925 -30.579 0.342 +10.13.1.11 .LOCL. 1 u 3 64 1 0.795 -31.123 0.077 [root@CompanyF5-3900U2:Standby:Changes Pending] configHowever because I have restarted the NTP service, the offset is considerably low. I will keep it under observation for 2-3 days and update the thread again with latest observation.
Thanks a ton Nitass for your extensive help mity! Much much appreciated!!
Cheers! Darshan