LTO Fiber/SCSI issues - read write issues 1

[dukbtr]

Hello,

We are preparing for our annaul DRP test at Sungard. We have had issues the last 2 years restoring with LTO tapes. We write to IBM Ultrium 1 drives (Fiber connected) in a STK L700e library, they are still direct connect to the media servers. At sungard we are given HP Ultrium 2 on Low Voltage Differential SCSI. In the past Sungard has tried to set up the LTO2 through a pathlight switch and direct connect and we have not been able to read from the tapes correctly.

This year we sent them a tape that we sent some Tar files to using HP-UX 11.11. Sungard was able to pull all the files off the tape at there sight for a drive test except for the 2Gig and up files. The Checksum and size were off. they read the files with the exact same procedure that we did here.

Is there some compatability issue with HP vs. IBM Drives, is the issue Fiber to SCSI, is it a combination of the two, is there something else going on?

Any help with this matter is greatly appreciated.

Thanks in advance,
Dukbtr

 

[comtec17]

It will not be an issue between fibre and SCSI because fibre channel only encapsulates SCSI commands.

This may be an issue between LTO2 drives reading LTO1 media. I would advise to tell Sungard to give you the exact hardware you are using to test with.

This could also be an issue with block size configured on the server that wrote the tape. By default, the block size is 64k, but to gain better performance most admins configured the drives to write in 256k blocks. If this is the case you will need to modify the tape configuration on the DR server.