The backup files are stored on piemonte under the directories /backup/systemname , for example "/backup/monviso". From the local system it appears as simply "/backup".
A typical name is monviso-020405.tar.gz , meaning it is a gzipped tar file made on 2002-April-5.
You must gunzip the file before you can untar it.
The tar file contains all the locally mounted filesystems. It does not contain remote filesystems, CD-ROMs, etc.
The tar file contains absolute paths . When you un-tar it, the files will overwrite your own files, since they will un-tar into absolute locations.
(Note: Absolute paths happen to be how we created our backup files; other tar files may have relative paths.)
The relevant tar commands are as follows. Note that important info regarding chroot is coming up.
tar tvf filename.tar |
(List the contents of the tar file) |
tar xvf filename.tar file1 file2 ... |
(extract the named files and directories) |
tar xvf filename.tar |
(extract and list the contents) |
tar xf filename.tar |
(extract the contents of the whole tar file, silently) |
In the form of the tar command to extract named files, you must put the full path as it appears in the tar file. In other words,
tar xvf
/etc/hosts would be correct, but not tar
xvf etc/hosts (wrong)
tar xvf hosts (wrong)
When in doubt, use a
If you name a directory to extract, it will take the whole directory subtree and all its files.
The chroot command exists to trick the tar command to write into relative locations:
chroot /tmp tar xvf tarfile.tar /space/mglass/proj1
This will extact the directory tree /space/mglass/proj1 and place it relative to /tmp, producing /tmp/space/mglass/proj1.
You must be logged in as root to run chroot.
Last Revised: 15 May 2002
Michael Glass