Environment
Novell ZENworks Desktop Management 7 - ZDM7 PreBoot Services
(PXE)
Novell Open Enterprise Server (Linux based)
Situation
If the date
shows Thu Aug 10 09:47:12 MDT 2006, then change the date to any
other date say one minute before with this commanddate
0810094606
NTP changing
the date back in time causes 100% utilization with
novell-xsrvd.
Resolution
Sync NDS replicas to a hardware box instead of a Virtual Machine box
Additional Information
Root Cause: Syncing DS
replicas to a master Virtual Machine box was causing the time to
drift in the future and constantly be reset back in
time.
The problem occurs more
readily on VMs because of the well-known issues keeping clocks
synced in a VM environment. Using kernel parameters such as clock=pit is enough to keep
the clock stable enough for xntpd to keep it in line, but it will
likely still have to make stepwise adjustments occasionally.
Normally, NTP will keep the clock in sync by "slewing" it - slowing
it down or speeding up as needed, but if the time difference is"large" (greater than 128ms by default), NTP will step the clock.
It was found that ntp on some VMs was doing this often enough, and
consequently causing XTier to flip out when doing a stepwise
adjustment backwards.
Fortunately, you can
force NTP to always adjust the time by slewing and never by
stepping the clock. To do so, add to ntp.conf:
tinker step 0
which specifies the clock difference in ms before NTP should apply a step instead of slewing. Setting to 0 disables step adjustments entirely.
tinker step 0
which specifies the clock difference in ms before NTP should apply a step instead of slewing. Setting to 0 disables step adjustments entirely.