How to BACKUP a 9G disk onto 2 5G tapes using only one tape drive

Since a 9G disk requires 2 tapes and we currently have only one node with 2 5G drives on it (UCCDFM), you have to do it as follows on any other node using one drive for both volumes. The examples below shows how to backup the 9G disk uccdfn$dka300 onto 2 tapes using the tape drive MKA400: on UCCDFN. This can be easily adapted for other nodes.

BACKUP has the advantage over COPY that it's much faster and more reliable (Marty claims he hasn't had any problems restoring files from tape using BACKUP).



1) become SYSTEM on UCCDFN (need privs for image backups)

2) Put the second tape into tapedrive MKA400:
    $ INIT/OVER=EXPIR MKA400: BACK02  
   Take out the second tape and put first tape into tapedrive MKA400:
    $ INIT/OVER=EXPIR MKA400: BACKUP  

3) $ MOUNT/FOREIGN MKA400:           - mount vol. 1

4) Start an image backup of the whole disk with complete directory structure:

    $ BACKUP/NOASSIST/IMAGE/REWIND/LOG/IGNORE=INTERLOCK/RECORD -
      DKA300:  MKA400:dka300.BCK,MKA400: -
      /BY_OWNER=ORIGINAL/SAVE_SET/LABEL=(BACKUP,BACK02)
   
5) After the first tape is full:

    The drive will open up. Take out the first tape and put the second 
    tape BACK02 in. The backup job will automatically mount the second tape 
    and then will continue to copy files.

6)  When the backup is complete:

     $ DISMOUNT MKA400:


To restore a file, mount the first tape (even if the file is on the second
tape) and use the command

$ BACKUP/REWIND/LOG - 
  MKA400:DKA300.BCK/SAVE_SET/SELECT=[DATA.CDF.ANA]myfile.ext;* -
  UCCDFN$DKA300:[DATA.CDF.ANA]myfile.ext/BY_OWNER=ORIGINAL/NEW_VERSION

This will restore the file on disk with a higher version number.

If the file is on the second tape, put in the first tape and wait until the job
has gone through it and the drive opens up. Then put in the second tape.


This handy advice brought to you by Marcus Hohlmann (hohlmann@uccdf.uchicago.edu) July 11, 96