Media write error

[nicowahoo]

Over the last weekend of full backups I experienced quite a lot of '84 Media write error' and '85 Media read error' messages.

Environment :
Veritas Netbackup Data Center 4.5fp3
Master Server - Windows 2000 SP3
4 Windows 2000 Media Servers
2 Solaris 8 Media Servers
StorageTek L700 tape library
2 Quantum DLT tape drives
4 Seagate LTO tape drives
4 HP Ultrium tape drives


Here are some of the logs on the Netbackup GUI :

Type : Media Device
Description : cannot position media id 007342 for write
Type : Backup
Description : INF - media read erro (85), cannot continue with copy 1
Type : Media Device
Description : write error on media id 007034, drive index 2, writing header block, 1117
Type : Backup
Description : INF - media write error (84), cannot continue with copy 2
Type : Backup Status
Decription : media write error


The backup environment is setup such that I make two copies of each job.

Also, I cannot understand why the media id 007034 which is an LTO2 tape is trying to use drive index 2 which is an LTO drive. The configuration is setup to use any of the free LTO2 tape drives.

I have tried to mutter through some logs, but cannot find and similarities that stand out. It doesn't appear to be associated with a particular tape drive or a particular tape.

The tapes are not write protected, so that is out.


Any suggestions???

 

[Stumpr]

Check the drive mapping of the device files to the correct physical drive.

Bob Stump
Incorrigible punster -- Do not incorrige

 

[nicowahoo]

Stumpr-

Thanks for your response.
Please explain more...

 

[Stumpr]

It is common for the error 84's to show up when the drives are not mapped correctly. The robot control puts the tape in the correct robot drive. However, the media server attempts to write to the drive but does not have the correct path and so it errors out stating that there was a media write error. In that case it is not so much a problem writing to the media as it is writing to the drive itself. The same is true for reading from a tape. If the path is not correctly defined then an error will occur. Check the mapping at the OS level.

Bob Stump
Incorrigible punster -- Do not incorrige