MADDISOJ@carleton.EDU (Joseph Maddison) (05/14/88)
In doing a backup of files on a disk to another disk, if the
directory where the files are to be placed doesn't exist,
then it will be created. This is all well and good. However,
when doing a tape backup of files on a disk, the directories
are unnecessary and waste space on the tape if you are
backing up large numbers of individual directories with files
in them. The intuitive solution of backup/exclude=(*.dir)
apparently does not work, presumably because BACKUP is
convince that it needs a directory to put the files in,
ignoring the sequential nature of the tape.
My question: are the directory files on tape as useless as
they seem? Is there a way to avoid them, if they are?
Joseph Maddison
Student Programmer/User Consultant
Carleton College
Northfield, MN 55057
maddisoj@carleton.edu (CSnet)
...!uwm-cs!stolaf!agnes!ccnfld!maddisoj (UUCP)
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I disclaim therefore I am not.
---------------------------------------------------------------------OBERMAN@ICDC.LLNL.GOV ("Kevin Oberman, LLNL, 422-6955, L-156", 415) (05/17/88)
> My question: are the directory files on tape as useless as > they seem? Is there a way to avoid them, if they are? No. Directories are NOT useless! They are absolutely essential to making incremental restores work. Incremental restore uses the most recent directory to determine what files from backup have been superceded and should be deleted or not restored. Since BACKUP never can tell when an incremental restore might be needed, it always saves the directories. R. Kevin Oberman Lawrence Livermore National Laboratory Internet: oberman@icdc.llnl.gov (415) 422-6955 Disclaimer: Don't take this too seriously. I just like to improve my typing and probably don't really know anything useful about anything.
kennedy@asuvax.UUCP (Ralph Kennedy) (05/19/88)
In article <8805161525.AA17245@ucbvax.Berkeley.EDU>, MADDISOJ@carleton.EDU (Joseph Maddison) writes: > My question: are the directory files on tape as useless as > they seem? Is there a way to avoid them, if they are? If a disk is lost and backups have been done correctly, during the restoration BACKUP/INCREMENTAL is smart enough to delete and/or not restore files that existed on earlier backups but that had been deleted by the user by the time some of the later backups had been taken. Without this feature the user would have to re-delete previously deleted files after the disk was restored. Even worse, if disk space were at a premium the disk might overflow before the restoration completed. This feature could not exist without BACKUP's meticulous recording of directory information; whether or not this recording can be disabled is left as an exercise for the manual reader. Ralph Kennedy {ames,husc6,rutgers}!ncar!noao!asuvax!kennedy Engineering Comp. Serv. {allegra,decvax,ihnp4,oddjob}!--^ Arizona St. Univ. Tempe, AZ 85287-5206 csnet: kennedy@asu.csnet
carl@CITHEX.CALTECH.EDU (Carl J Lydick) (05/24/88)
> In doing a backup of files on a disk to another disk, if the > directory where the files are to be placed doesn't exist, > then it will be created. This is all well and good. However, > when doing a tape backup of files on a disk, the directories > are unnecessary and waste space on the tape if you are > backing up large numbers of individual directories with files > in them. The intuitive solution of backup/exclude=(*.dir) > apparently does not work, presumably because BACKUP is > convince that it needs a directory to put the files in, > ignoring the sequential nature of the tape. > > My question: are the directory files on tape as useless as > they seem? Is there a way to avoid them, if they are? Backup copies the directories to tape so that it knows: 1) What the file attributes, protections, etc. are supposed to be for the directories, for when you restore the files to disk (in case you restore them to a different place, or the directories were deleted between your backup and restore); and 2) So incremental backups leave you with only the files that existed when the incremental backup was performed. You can't force it to leave out all the directories.