IDS Forum

RE: Ontape to backup Logical logs - Query

Posted By: Penza Kenneth at MITA
Date: Wednesday, 18 February 2009, at 8:32 a.m.

In Response To: Ontape to backup Logical logs - Query (VIKAS HIVARKAR)

Vikas,

May I suggest that you look into the command flock instead of
"ps -aef | grep "ontape -a -d" |grep -v grep |". Flock allows you to run
just one command at a time.
Example: flock -x /var/lock/informix_<instancename> ontape -a -d
Thus if the alarmprogram triggers another logbackup it will have to wait
for a lock on the file to be released and the lock is released only when
ontape exits. I guess this should solve the problem of con-current
ontapes.

Regards,
Kenneth Penza
Systems Engineer| SMD
MALTA INFORMATION TECHNOLOGY AGENCY
* email: kenneth.penza@gov.mt - ( Office: +356 2599 2867 :
http://www.mita.gov.mt
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-----Original Message-----
From: ids-bounces@iiug.org [mailto:ids-bounces@iiug.org] On Behalf Of
VIKAS HIVARKAR
Sent: 18 February 2009 10:58
To: ids@iiug.org
Subject: Ontape to backup Logical logs - Query [14927]

Hello,

IDS 11.10.FC3 on solaris 10.

#Please consider this as a query and not a problem yet.
#I know the my logical logs are small in size(500+, 20M each) for taking
some
hectic transactions BUT not possible to to increase the log size atleast
for
now.

In 11.10.FC2W4 i faced a bug with parallel ontapes running for backing
up the
logical logs & resulting in Loss of logical logs files.
(ontape to directory feature used. Alarmprogram.sh to backup the logs)

One of the workaround was to check if ontape is running, some thing
like:
"ps -aef | grep "ontape -a -d" |grep -v grep |" in the alarmprogram.sh
script
before a new ontape is invoked.

I did all this in order to avoid new ontape when one is already in
progress.

Now I have 11.10.FC3 with the bug fix, the first thing i checked in my
testings was the name for temp file which now i see unique for every
temp file
generated/used by ontape before writing to permanent file on the disk.

I also see that now IDS is not allowing another ontape to run untill one
is
already running: (May be i am not correct on this).
------ontape's output---------
Performing automatic backup of logical logs.

Logbackup failed - A Log backup is already in progress.

Program over.

Performing automatic backup of logical logs.

Logbackup failed - A Log backup is already in progress.
-----------------------------
Thanks to detailed explanation by Martin, I understand that the ontape
which
is already running would backup all the logs that are filled & are
available
to be backed up, infact it would check if another log is near to
complete so
that it can also be backed up. So Every logical log file would be backed
up.

BUT it worries me when i see:

3180dd9e8 342 U-B---- 64216 5:3290053 10000 10000 100.00
3180dda50 343 U-B---- 64217 5:3300053 10000 10000 100.00
3180ddab8 344 U-B---L 64218 5:3310053 10000 10000 100.00
3180ddb20 345 U-B---- 64219 5:3320053 10000 10000 100.00
3180ddb88 346 U------ 64220 5:3330053 10000 10000 100.00
3180ddbf0 347 U------ 64221 5:3340053 10000 10000 100.00
3180ddc58 348 U------ 64222 5:3350053 10000 10000 100.00
3180ddcc0 349 U------ 64223 5:3360053 10000 10000 100.00
3180ddd28 350 U------ 64224 5:3370053 10000 10000 100.00
3180ddd90 351 U------ 64225 5:3380053 10000 10000 100.00
3180dddf8 352 U------ 64226 5:3390053 10000 10000 100.00
3180dde60 353 U------ 64227 5:3400053 10000 10000 100.00
3180ddec8 354 U------ 64228 5:3410053 10000 10000 100.00
3180ddf30 355 U------ 64229 5:3420053 10000 10000 100.00
3180ddf98 356 U------ 64230 5:3430053 10000 10000 100.00
3180de028 357 U------ 64231 5:3440053 10000 10000 100.00
3180de090 358 U------ 64232 5:3450053 10000 10000 100.00
3180de0f8 359 U------ 64233 5:3460053 10000 10000 100.00
3180de160 360 U------ 64234 5:3470053 10000 10000 100.00
3180de1c8 361 U------ 64235 5:3480053 10000 10000 100.00
3180de230 362 U------ 64236 5:3490053 10000 10000 100.00
3180de298 363 U------ 64237 5:3500053 10000 10000 100.00
3180de300 364 U------ 64238 5:3510053 10000 10000 100.00
3180de368 365 U------ 64239 5:3520053 10000 10000 100.00
3180de3d0 366 U------ 64240 5:3530053 10000 10000 100.00
3180de438 367 U------ 64241 5:3540053 10000 10000 100.00
3180de4a0 368 U------ 64242 5:3550053 10000 10000 100.00
3180de508 369 U------ 64243 5:3560053 10000 10000 100.00
3180de570 370 U------ 64244 5:3570053 10000 10000 100.00
3180de5d8 371 U------ 64245 5:3580053 10000 10000 100.00
3180de640 372 U---C-- 64246 5:3590053 10000 4107 41.07
3180de6a8 373 U-B---- 63661 5:3600053 10000 10000 100.00
3180de710 374 U-B---- 63662 5:3610053 10000 10000 100.00
3180de778 375 U-B---- 63663 5:3620053 10000 10000 100.00
3180de7e0 376 U-B---- 63664 5:3630053 10000 10000 100.00

What if now the engine goes down?

Sure Ontape is running and would backup all these files.
Sure my logical log size needs to be increased atleast to 100M(i had to
convience a lot to increase it from 5M to 20 M and still working to get
it
atleast 100M).
Sure IDS is working as it designed to work.

With the fix as unique names for temp files i was under wrong impression
that,
now ontape(s) now can run parallely with out over writing each others
temp
files and backup the logs, instead of one running and doing all the
work.

May be i'm totally wrong here hence Any information regarding this is
appreciated.

Regards,
Vikas

P.S: Better to read than to fall in guesstimation but i dont know if
there are
any documents released/written explaining the change made.

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Messages In This Thread

• Ontape to backup Logical logs - Query
  VIKAS HIVARKAR -- Wednesday, 18 February 2009, at 4:57 a.m.
  • Re: Ontape to backup Logical logs - Query
    Martin Fuerderer -- Wednesday, 18 February 2009, at 5:27 a.m.
    • Re: Ontape to backup Logical logs - Query
      VIKAS HIVARKAR -- Wednesday, 18 February 2009, at 6:30 a.m.
      • Re: Ontape to backup Logical logs - Query
        rroussey@comcast.net -- Wednesday, 18 February 2009, at 1:54 p.m.
  • RE: Ontape to backup Logical logs - Query
    Penza Kenneth at MITA -- Wednesday, 18 February 2009, at 8:32 a.m.
  • Re: Ontape to backup Logical logs - Query
    Art Kagel -- Wednesday, 18 February 2009, at 11:39 a.m.

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