Validate backup : archecker –tdsv and CommVault
Posted in 2021
Sh To wanted to validate a CommVault backup with archecker -tdsv and got a tape device error. Mike Walker and Paul Watson said onbar needs -b, not -t; onbar -v simply runs archecker. archecker -bdsv validated nothing, while onbar -v on one 581 GB dbspace took about 12 hours at roughly 41 GB/hour, which Art Kagel judged slow storage and said the test passed. Eric, Paul and Art recommended PSM to local disk.
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Topics: General Discussion
Hello, I'd like to validate a backup with archecker ‑tdsv but in front of CommVault If i run it as is i get Error(2) opening tape device(/commv_dev/tmp0) On the same machine, a table restore with commvault works with this command Advanced Restore archecker -Xbvs -f cmdfile Does someone have an idea how to fit archecker ‑tdsv with Commvault ? Thanks ------------------------------ Sh To ------------------------------ #Informix
If you are using onbar, then the options to archecker should be -b, not -t (that's for ontape).
So command should be: archecker -bdsv
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Mike Walker
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Try –b. Commvault uses onbar AFAIK. You used –b in the restore command
Cheers
Paul
Mike and Paul thanks a lot.
I saw that
onbar -vcan do the job
Are you aware of any efficiency difference between
onbar -vand
archecker ‑
b
dsv
Cheers
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Sh To
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I am not aware of any difference, and I believe that "onbar -v" will simply execute archecker.
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Mike Walker
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Thanks ------------------------------ Sh To ------------------------------
Mike is correct. onbar -v is just a shortcut to run archecker to validate an onbar archive.
Art
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Art S. Kagel, President and Principal Consultant
ASK Database Management Corp.
www.askdbmgt.com
------------------------------
The same thing, I suppose archecker is quicker as onbar is just a wrapper but you would never be able to measure the difference
Cheers
Paul
Hello,
So
archecker -bdsv runs but apparently doesn't do a lot.
I get instantaneously
ids1:/IDS/informix$archecker -bdsv
IBM Informix Dynamic Server Version 12.10.FC10
Program Name: archecker
Version: 8.0
Released: 2017-10-23 13:02:19
CSDK: IBM Informix CSDK Version 4.10
ESQL: IBM Informix-ESQL Version 4.10.FC9
Compiled: 10/23/17 13:02 on Linux 2.6.18-128.el5 #1 SMP Wed Dec 17 11:41:38 EST 2008
AC_STORAGE /tmp
AC_MSGPATH /tmp/ac_msg.log
AC_VERBOSE on
AC_TAPEBLOCK 62 KB
AC_IXBAR /IDS/informix/etc/ixbar.0
AC_TIMEOUT 300
AC_SESSION
Control page checks PASSED
Table checks PASSED
Tables/Fragments validated: 0
ids1:/IDS/informix$
And that s all.
On the other hand
onbar -vseems to do the job
ids1:/IDS/informix/restore$onbar -v
onbar is starting ..........
Galaxy Instance: Instance001
Loading Library:/opt/commvault/Base64/libCvIbsad.so from dir /opt/commvault/Base64
Get object = /ids1/rootdbs/0
Data transfer Complete, total = 91613184 bytes
File /ids1/rootdbs/0.1612897233.27085 Size = 91613184 bytes, Informix I/O Time = 7.337244 secs, MA I/O Time = 0.374616 secs, Total I/O Time = 7.711860 secs,Informix Throughput = 41.862740 GB/Hr, MA I/O Throughput = 819.925297 GB/Hr, Total I/O Throughput = 39.829190 GB/Hr
Get object = /ids1/dblog/0
Data transfer Complete, total = 63488 bytes
File /ids1/dblog/0.1612911854.27085 Size = 63488 bytes, Informix I/O Time = 0.000130 secs, MA I/O Time = 0.139186 secs, Total I/O Time = 0.139316 secs,Informix Throughput = 1637.385442 GB/Hr, MA I/O Throughput = 1.529321 GB/Hr, Total I/O Throughput = 1.527894 GB/Hr
It did rootdbs, dblog, and other 7 small dbspaces
but it took a long time.
It started a smartblob dbspace (dbsb) at 8:22 (tmp/
bar_act.log
)
2021-02-10 08:22:24 55006 55004 Begin backup verification of level 0 for dbsb (Storage Manager copy ID: 27085 1612897235).
And 11 hours after it failed
2021-02-10 19:11:26 6684 6644 onbar_d -b -l
2021-02-10 19:11:26 6684 6644 Working with cvsm as generic storage manager.
2021-02-10 19:11:26 6684 6644 onbar_d complete, returning 0 (0x00)
2021-02-10 08:22:24* 55006 55004 (-43080) Process 55006 received signal 15. Process will exit after cleanup.
2021-02-10 19:15:25 55006 55004 Unable to write storage space restore data to the database server: .
2021-02-10 19:15:37 55006 55004 /IDS/informix/bin/onbar_d complete, returning 131 (0x83)
I will try to run onbar dbspace by dbspace, but the question is why this is so long.
The same DB, on a dev server backed up with ontape on NAS was validate with
archecker ‑tdsv
in 2 hours
I wander if there is a problem, or it s like this with commvault
Does someone out there use Commvault and have some advices ?
Thanks
------------------------------
Sh To
------------------------------
Signal 15 is SIGTERM - some other process or session killed the onbar session or the underlying archecker session. The bar_debug file might have more detail.
------------------------------
Art S. Kagel, President and Principal Consultant
ASK Database Management Corp.
www.askdbmgt.com
------------------------------
I have a customer at which we tested Commvault direct to onbar, but at the end it remained very slow even playing with onbar onconfig parameters.
At the end we decided to use PSM, then comvault takes the PSM files as normal file systems. => backup is done much quicker and you depend less on Commvault to restore.
The caveat of this method is that you need more file system space if you want to keep several backup generations on line
In general, backing up to a Enterprise backup system like Commvault may save money to the company, but when it comes to restoring, Informix becomes one client among many clients in the company and you may be very disappointed in terms of priority for restoring. This happened at another customer where he had to wait for hours before he could restore his backup, because other clients were backing up at this time...
Backing up with PSM on local FS then push to Enterprise system later may offer more versatility.
Hello Yes, i saw that... and i don't know what happened . Unfortunately the BAR_DEBUG is off (0) But it's still very long ... I'll enable bar_debug and see what happens. Thanks ------------------------------ Sh To ------------------------------
Totally agree, back up to local disk first and the get Commvault or whatever to pick up the files. My real-world example was the company that lost the Enterprise backup server and it took 3 days to get it rebuild and fully functional. And of course when this happened they also needed a production restore. Kinda ironic that the company was down for over a day cos their backup system failed. Cheers Paul
Can you say "single point of failure"?
I always recommend using ontape or onbar with PSM to archive to local disk then have the Enterprise backup system sweep the files to near-offline storage while keeping one or two local archives! Then there IS NO SINGLE POINT OF FAILURE that could prevent a timely restore!
Art
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Art S. Kagel, President and Principal Consultant
ASK Database Management Corp.
www.askdbmgt.com
------------------------------
Hello
So I ran for test a validation on only one dbspace (dbsb), its size is 581 GB and it took apparently about 12 hours!!
Is this representing the time that a restore could take?
Just a question about the result… I can see "Data transfer Complete, total = 581776986112 bytes"
But I would expect "Data
verification
Complete…"
This means that all is OK?
ids1:/IDS/informix$onbar -v dbsb
onbar is starting ..........
Galaxy Instance: Instance001
Loading Library:/opt/commvault/Base64/libCvIbsad.so from dir /opt/commvault/Base64
Get object = /ids1/dbsb/0
Data transfer Complete, total = 581776986112 bytes
File /ids1/dbsb/0.1612897235.27085 Size = 581776986112 bytes, Informix I/O Time = 45812.253628 secs, MA I/O Time = 909.040381 secs, Total I/O Time = 46721.294009 secs,Informix Throughput = 42.577241 GB/Hr, MA I/O Throughput = 2145.734542 GB/Hr, Total I/O Throughput = 41.748830 GB/Hr
About the PSM, I have to start from here ?
https://www.ibm.com/support/knowledgecenter/en/SSGU8G_12.1.0/com.ibm.bar.doc/ids_bar_533.htm
Thanks
------------------------------
Sh To
------------------------------
Validation is far more involved than a restore is, so it should be faster. However, look at the IO rate! 41gb/hour is about 0.7gb/min or 130mb/sec which is about half the transfer rate of a single 5000rpm spindle drive. So the storage itself or the storage manager you are using ate slowing you down! FWIW, "Yes" to your other questions. The test went well. No problems detected. Also, that article should get you started with PSM. ------------------------------ Art S. Kagel, President and Principal Consultant ASK Database Management Corp. www.askdbmgt.com ------------------------------