DLT tape movement using rmt

[baggetta]

Does anyone know what the following commands do when you are doing a PROREST (progress restore from tape)?
rmt0.1
rmt0.5
etc...
I'm having some problems when it restores the 2nd db, its not starting up.

 

[KenCunningham]

Hi. man rmt gives the various options for the device. HTH.

 

[baggetta]

Thanks for that "tip" but, it doesn't help, there is nothing in the man rmt that describes how these commands work.

 

[KenCunningham]

Hmm, I agree it's probably not the most eloquent man page ever, however:

Tape Drive Special File Characteristics

Special File Name Rewind-on-Close Retension-on-Open Bytes per Inch

/dev/rmt* Yes No Density setting #1

/dev/rmt*.1 No No Density setting #1

/dev/rmt*.2 Yes Yes Density setting #1

/dev/rmt*.3 No Yes Density setting #1

/dev/rmt*.4 Yes No Density setting #2

/dev/rmt*.5 No No Density setting #2

/dev/rmt*.6 Yes Yes Density setting #2

/dev/rmt*.7 No Yes Density setting #2

does at least give you a clue. Using your examples:

rmt0.1 will rewind on the close of a save, but not retension the tape when it is opened for writing. rmt0.5, on the other hand will not rewind the tape at the end of a save and will not retension it when opening for a save. As far as density settings #1 and #2 are concerned, the man page has this to say:

" 1. The values of density setting #1 and density setting #2 come from tape drive attributes that can be set using SMIT. Typically density setting #1 is set to the highest possible density for the tape drive while density setting #2 is set to a lower density. However, density settings are not required to follow this pattern."

HTH.

 

[KenCunningham]

My apologies /dev/rmt0.1 will NOT rewind on close as said above. It's been a long and hot (for a change!) day. Time for a beer methinks.

 

[baggetta]

Thanks for that info, I actually found the same data from the IBM webpages.
We can't figure out why our db doesn't want to start after a progress restore from tape. Sometimes it does, majority of the time it doesn't. I'm even using new tapes, cleaning the drives etc....I need to test a restore from tape as a tar backup of the db, then restore the tar files to disk, then see if it works. If it does, then all these new tapes are bad...go figure.

 

[baggetta]

Ken, do you know how to extract file from tape using tar but, extract them to a different folder?
I tried using: tar -xvf /dev/rmt0 /home/rico -C /home/rico2

This still extracts the files to /home/rico.

 

[jie]

Hey baggetta try this thread it might help thread 52-535904

For example, suppose you receive a tar tape created using absolute path names: tar -cvf /dev/rmt0 /work/*
but want to restore it to the /test directory.

The pax command would be:
pax -rf /dev/rmt0 -s/work/test/p
The -s/work/test/p does the directory change.

This tip came from vivek1712 ..

 

[baggetta]

Thanks for all the replies, I found that I was not backing up the file names with a relative path, hence, I could not restore them to a different folder.
Relative path in the tar listing should have a "." in front of the file. This how I did the backup/restore with tar.
BACKUP:
cd /home/folder1
tar -cv -C . file1 file2 (this will only backup these files)

RESTORE:
cd /home/folder5
tar -xv file1
cd /home/folder6
tar -xv file2

pax was not that great because my tar list has subfolders.
ie: /home/folder1
How would I replace the above with "/apps/backup1" using pax. Don't know, didn't care.
r