Error 102 Problem & Direct Block Locate

[dl_caldwell]

Hello Everyone,

 

 

 

I have been having significant intermittent problems restoring data from my backup tapes ever since upgrading to Retrospect Server 5.5 (and 5.6). The restore will proceed fine for a while, it will start seeking a file and die with the following message:

 

 

 

"102 Error Communicating"

 

 

 

While troubleshooting this with Dantz tech support I was taken to the "Secret Preferences" pane. I changed some settings in there to no avail. Dantz concluded we had bad tapes and closed the issue. After getting different tapes the problem reappeared. I went in and started troubleshooting this using some of the options in the "Secret Preferences" pane.

 

 

 

There was one option that fixed the problem:

 

 

 

1. Go into the "Secret Preferences" panel

 

2. Select "Device Driver"

 

3. Uncheck "Direct Block Locate"

 

 

 

With this option changed Retrospect now happily restores my data. Why? What does this option do? What are the consequences of disabling it?

 

 

 

I've had this problem on two different backup servers, with different DLT Autoloaders, different SCSI Adapters, etc. So I doubt if it is a hardware problem.

 

 

 

Any input or insight would be much appreciated!!

 

 

 

 

[lv2ski]

This option has been used. Here is what it does.

 

 

 

Direct Block Locate uses a "space forward n blocks" type of command

 

instead of locating to a filemark with streaming tape drives.

 

 

 

By turning this option off, you have the potential of restoring

 

successfully because we are going to go straight for the filemarks

 

instead of moving "x" amount of block spaces forward. It is slower. This is why it not on by

 

default. If 1 block is out of sequence, or a filemark is written in the

 

wrong place it can mess up a tape, so this option should only be used

 

with "Streaming" tape drives.

 

 

 

Hope this helps.

[dl_caldwell]

I've encountered this error on two separate backup servers with different DLT autoloaders. A HP DLT1/9 and an older HP DLT4000. This problem has been driving me up a wall for several months now. Any idea what would cause a problem like this? Why it has only showed up since we upgraded to Retrospect Server 5.5 (and 5.6).

 

 

 

We used previous versions of Retrospect Server for more than a year without ever having this problem.

 

 

 

Thanks for your reply!