PAUSE
HILINE
GO
COMPARISON OF BACKUP & RESTORE PROGRAMS
-------------------
|DISK |
| |
|filesystem A |
| |
| filesystem B |
| |
| filesystem C |
| |
|filesystem D |
| |
| filesystem E |
| |
-------------------
When you backup a file system with tar or cpio,
-------------------
|DISK |
| |
|filesystem A |
| |
| filesystem B | ____
| | / \
| filesystem C |------->|tar/cpio|
| | | tape |
|filesystem D | \ ____ /
| |
| filesystem E |
| |
-------------------
the restored file system is not guaranteed to go back to the same
place on the disk. You can restore it wherever it best fits on
your system.
------------------- --------------------
|DISK | | filesystem C |
| | /| |
|filesystem A | / |filesystem A |
| | / | |
| filesystem B | ____ / | filesystem B |
| | / \ / | |
| filesystem C |------->|tar/cpio| / | filesystem C |
| | | tape |/ | |
|filesystem D | \ ____ / |filesystem D |
| | | |
| filesystem E | | filesystem E |
| | | DISK |
------------------- --------------------
The volcopy utility makes a picture image,
COMPARISON OF BACKUP & RESTORE PROGRAMS
-------------------
|DISK |
| |
|filesystem A |
| |
| filesystem B | ____
| | / \
| filesystem C |------>|volcopy |
| | | tape |
|filesystem D | \ ____ /
| |
| filesystem E |
| |
-------------------
so when the file system is restored, it goes back
to exactly the same place.
------------------- --------------------
|DISK | |DISK |
| | | |
|filesystem A | |filesystem A |
| | | |
| filesystem B | ____ | filesystem B |
| | / \ | |
| filesystem C |------->|volcopy |------>| filesystem C |
| | | tape | | |
|filesystem D | \ ____ / |filesystem D |
| | | |
| filesystem E | | filesystem E |
| | | |
------------------- --------------------
When you use dump or backup,
COMPARISON OF BACKUP & RESTORE PROGRAMS
-------------------
|DISK |
| |
|filesystem A |
| |
| filesystem B | ____
| | / \
| filesystem C |------>| dump |
| | | tape |
|filesystem D | \ ____ /
| |
| filesystem E |
| |
-------------------
you can backup individual files or an entire file system. Files
can be restored onto any file system but an entire file system can
be restored on top of an existing file system; therefore you have
to be sure not to overwrite another necessary file system.
------------------- --------------------
|DISK | |DISK |
| | | |
|filesystem A | |filesystem A |
| | | |
| filesystem B | ____ | filesystem B |
| | / \ | |
| filesystem C |------->| dump |------>| filesystem C |
| | | tape | | |
|filesystem D | \ ____ / |filesystem D |
| | | |
| filesystem E | | filesystem E |
| | | |
------------------- --------------------