topic system timezone change problem with RAC in Operating System - HP-UX

system timezone change problem with RAC

borut kurnik_1 — Wed, 20 Dec 2006 04:22:22 GMT

Hi!

I've got two hp-ux ia64 (11.23) nodes running
Oracle 10.2.0.2 RAC.

At system inst. on one of then i set time zone
MST by mistake. Should have been MET.

At the time nodes were not configured as NTP clients yes, so I didn't notice that until after RAC was up and running.

I changed it and now I have a big problem.

Oracle instance on that node still shows the
MST time (TO_CHAR(SYSDATE,...)).

After the system timezone change I rebooted
the system.

Then I set:
# srvctl getenv database -d hb0
TNS_ADMIN=/cfs/sw01/ora/10.2.0/db1/network/admin
TZ=+01:00

# I set Oracle's TZ variable (listener
runs under oracle user) to the same
value, restarted instance + crs on
that node ...

Nothing seems to help.

Any ideas, please?

Thanks,

Borut

Re: system timezone change problem with RAC

Sunil Sharma_1 — Wed, 20 Dec 2006 04:44:10 GMT

Borut,

You may need to change the time zone at Unix level as well. Try set_parms coomand to change your syste's time zone. This require system reboot so be careful.

Sunil

Re: system timezone change problem with RAC

borut kurnik_1 — Wed, 20 Dec 2006 04:50:10 GMT

Hi!

Thanks, Sunil.

I've already done that.

In fact, that wast the cause of
it all. I had to change timezone from
MST to MET at the HP-UX level
first, so I did it (and of course
rebooted the system).

Just the Oracle RAC instance on
that node doesn't seem to
'understand' that, so the time
it shows is still MST.

Regards,

Borut

Re: system timezone change problem with RAC

Eric Antunes — Wed, 20 Dec 2006 06:46:57 GMT

Hi borut,

The HP-UX $TZ precedences are (see patch PHCO_34275 special instructions for better understanding):

1) if the environment variable TZ is present, it takes the
precedence.
2) if TZ is not present, then the value contained in
/etc/default/tz is used for default.
3) if /etc/default/tz is not set, then the default value is
equivalent to EST5EDT (Eastern Standard Time) of US.

Best Regards,

Eric

Re: system timezone change problem with RAC

Eric Antunes — Wed, 20 Dec 2006 06:56:44 GMT

[cont.]

...So how did you set the $TZ variable?

TZ is not an Oracle variable but an HP-UX one and if not set explicitly will default to the value in "/etc/default/tz".

ORA_TZFILE is usally used for Oracle:

export ORA_TZFILE="$ORACLE_HOME/oracore/zoneinfo/timezlrg.dat"

Best Regards,

Eric Antunes

Re: system timezone change problem with RAC

borut kurnik_1 — Wed, 20 Dec 2006 07:08:24 GMT

Hi!

Thanks, Eric.

My HP-UX timezones are ok (MET) now. I have
no problem there.

The only problem is that Oracle instance on
the node where timezone was incorrect, still
shows the wrong time.

system node1:
=============
# date
Wed Dec 20 12:53:17 MET 2006

system node2:
=============
# date
Wed Dec 20 12:53:23 MET 2006

oracle instance system 1:
=========================
SQL> select dbtimezone from dual;
DBTIME
------
+00:00

SQL> select sessiontimezone from dual;
SESSIONTIMEZONE
---------------
+01:00

SQL> select to_char(sysdate,'YYYYMMDD HH24:MI:SS') from dual;

TO_CHAR(SYSDATE,'
-----------------
20061220 12:54:12

oracle instance at system 2:
============================
SQL> select dbtimezone from dual;
DBTIME
------
+00:00

SQL> select sessiontimezone from dual;
SESSIONTIMEZONE
---------------
+01:00

SQL> select to_char(sysdate,'YYYYMMDD HH24:MI:SS') from dual;

TO_CHAR(SYSDATE,'
-----------------
20061220 06:54:17

As you can see, the both systems
show the same time and timezone
settings, but the Oracle instances
show the same timezone setting but
different time and
the difference between the instances is
6 hrs, which is the difference between
MET and MST.

Regards,

Borut

Re: system timezone change problem with RAC

borut kurnik_1 — Wed, 20 Dec 2006 08:08:45 GMT

Thanks, guys!

Re: system timezone change problem with RAC

Hung Pham — Fri, 26 Jan 2007 12:05:45 GMT

Borut,

Did you resolve this issue? If yes, could you share what you did to fix this problem (ie, how to get Oracle to recognize system timezone)?

Thanks,
HP

Re: system timezone change problem with RAC

borut kurnik_1 — Fri, 26 Jan 2007 16:14:05 GMT

Hi!

Oh yes, of course. Sorry.

As Eric wrote ....

1) if the environment variable TZ is present, it takes the
precedence.
2) if TZ is not present, then the value contained in
/etc/default/tz is used for default.
3) if /etc/default/tz is not set, then the default value is
equivalent to EST5EDT (Eastern Standard Time) of US.

I updated /etc/default/tz, but I also had
TZ set in one of those nested login procedures.

Just wasn't careful enough...

Regards,

Borut