Microsoft KB Archive/46105

Restoring BACKUP Disks Out of Sequence PSS ID Number: Q46105 Article last modified on 03-02-1993 PSS database name: O_MSDOS

3.30 3.30a 4.00 4.01

MS-DOS

Summary:

If a file backed up with the BACKUP utility is spread out over more than one BACKUP disk, and you attempt to RESTORE files starting with a disk that the file does not start on but fully occupies, then RESTORE terminates if the next disk is a disk that the same file fully occupies. One workaround is to start the RESTORE process with either the disk that the file starts on or the disk that the file ends on.

More Information:

Suppose you have backed up some very large files up to several disks so that the files are spread out similar to the following:

Disk 1: FILE1 FILE2 (only part of it) Disk 2: FILE2 (more of it) Disk 3: FILE2 (rest of it) FILE3 (only part of it) Disk 4: FILE3 (more of it) Disk 5: FILE3 (more of it) Disk 6: FILE3 (the remainder) FILE4 FILE5

If you execute RESTORE (i.e., RESTORE A: C:*.* /S) with Disk 2 as the starting disk, RESTORE will issue a warning. If you choose to continue, RESTORE will attempt to restore the file. In this case, since FILE2 started on Disk 1, RESTORE will NOT restore it. It will scan to the end of Disk 2 and prompt for Disk 3. Now, since Disk 3 has the the rest of FILE2, RESTORE will ignore it. However, since it found FILE3 on that disk, it will attempt to restore it and RESTORE should function successfully.

If you start RESTORE with Disk 4 instead of Disk 2, RESTORE will find only FILE3 on it and not RESTORE it. RESTORE will then prompt for the next disk and will terminate without asking for the next disk because Disk 5 has only one file.

In such a situation, you can RESTORE the other files (FILE4 and FILE5) if RESTORE is started out of sequence on Disk 6. The remnants of FILE3 in Disk 6 will not be RESTOREd and will therefore be ignored.

The only way FILE3 can be RESTOREd is to RESTORE the file from Disk 3.

Additional reference words: 3.30 3.30a 4.00 4.01 noupd

Copyright Microsoft Corporation 1993.