errors in the backup of linux clients

[sunboy]

Hi,

I have the following problem:

The backups of linux clients finish with code 1 (warning), with errors of the following type:

"from client clientXX: ERR - File /lib/ld-2.3.2.so shrunk by 108512 bytes, padding with zeros"....

Master and media server : Solaris 8 (64) Veritas NetBackup DC 4.5 MP6
Linux client: Redhat AS 3.0 ( linux 2.4) VNB 4.5_FP6

Can somebody help me?

Thank in advance,

Jorge Prado T.

 

[Stumpr]

All log entries for the client show an error message after performing backups.

http://support.veritas.com/docs/243657

Exact Error Message
"error: files shrunk padding with zeros"

Details:
The "file xxx shrunk by x bytes padding with zeros" message says that the file was modified to be a smaller size between the time of the start of the file backup and the time of the completion of the file backup.

VERITAS NetBackup (tm) determines the file has changed by running the lstat command. This is done to determine the file size just before starting the backup of the file. At the end of that file backup, lstat is run again to compare the size of the two lstat returns. If the second lstat is smaller than the first, it can be determined that the file was modified during backup.

On Solaris 8 (64 bit) platforms, apply Sun patch 109384-03 or later to fix Sun BugID # 4502769 that also causes this issue with "file xxx shrunk by x bytes padding with zeros." If you apply Sun patch 109384, and are using the NetBackup workaround in TechNote 240652 (link in Related Documents section of this TechNote) for this bug, refer to the TechNote again and delete the /usr/openv/netbackup/AIO_READS_MAX file.

Related Documents:

240652: When using VERITAS NetBackup 3.4.x on Solaris 8 (64 bit only), using VERITAS File System (tm) or UNIX File System, the backup operation completes with error Status 1, with the errors in the bpbkar log.

http://support.veritas.com/docs/240652

Bob Stump
Just because the VERITAS documentation states something as certain, that does not make it a fact and that is truth.

 

[Stumpr]

When using VERITAS NetBackup 3.4.x on Solaris 8 (64 bit only), using VERITAS File System (tm) or UNIX File System, the backup operation completes with error Status 1, with the errors in the bpbkar log.

http://support.veritas.com/docs/240652

Exact Error Message
file xxx shrunk by x bytes padding with zeros

Details:
During a backup operation, files are reported to be padded with zeros by NetBackup. The files can become corrupted. Client compression is disabled.

Extract from the bpbkar log:

2/9/01 hfxcdb4 22360 0 0 caprd bpbrm from client caprd: ERR- File /u22/oradata/db9888/IMAGES012_04.dbf shrunk by 2203276800 bytes, padding with zeros (R/0)
4/9/01 hfxcdb4 22991 0 0 caprd bpbrm from client caprd: ERR - File /u11/oradata/db9888/IMAGES025_03.dbf shrunk by 662074880 bytes, padding with zeros (R/W)
hfxcdb4 23001 0 0 caprd bpbrm from client caprd: ERR - File /u29/oradata/db9888/arch/ARC0000260502.LOG shrunk by 5861376 bytes, padding with zeros (ARCH)
hfxcdb4 bpbrm from client hfxcdb4: ERR - File /var/sadm/pkg/SUNWxwplt/save/108652-18/undo.Z shrunk by 1298593 bytes, padding with zeros (Non DB)
10/9/01 hfxcdb4 24280 0 0 caprd bpbrm from client caprd: ERR - File /u11/oradata/db9888/IMAGES025_01.dbf shrunk by 11768188416 bytes, padding with zeros (R/W)


The resulting backup will fail with status one and the files will be corrupted.

This issue is related to Sun BugID #4502769 with asynchronous IO on Solaris 8 - 64 bit, the Sun posix4 aio implementation. The problem is due to a bug in the libaio binary in Solaris, which can, for example in the case of NetBackup 3.4, cause the backup to think Solaris has finished reading file data when in fact it has not.

The NetBackup workaround before the Sun patch release was to disable asynchronous I/O for NetBackup. This was done by creating the file /usr/openv/netbackup/AIO_READS_MAX. Place a value of 1 in the file to turn off asynchronous I/O. This can impact the speed of the backups and may require tuning until the Sun patch can be applied.

On Sun Solaris 8 (64 bit) platforms, apply Sun patch 109384-03 or later to fix Sun Bug # 4502769 that causes this issue with "file xxx shrunk by x bytes padding with zeros." If Sun patch 109384-03 or later is applied and the NetBackup workaround in this TechNote is being used, delete the /usr/openv/netbackup/AIO_READS_MAX file.

To obtain this patch, contact Sun:

Worldwide Sun support numbers:

http://www.sun.com/contact

Obtain Sun patches and patch details:

http://sunsolve.sun.com

Bob Stump
Just because the VERITAS documentation states something as certain, that does not make it a fact and that is truth.