Creating a bootable disk with a non-image backup

[Dom Searle_1]

I have restored a system disk from a non-image backup.

I then ran the sys$system:writeboot to my restored image. The write boot fails "vmb.exe not contigious".

Can any one help me, or provide me with some info on making a bootable system disk from a non-image backup ?

Thanks for your help,

[Ian Miller.]

did you init the disk before restoring the backup? Is VMB.EXE contiguous (do DUMP/HEAD/BLOCK=COUNT=0 SYS$SYSTEM:VMB.EXE and if contig then there will be only one entry in the map area of the file header.

COPY /CONTIGUOUS VMB.EXE VMB.EXE should make it so. However there may be other problems.

[John Gillings]

>COPY /CONTIGUOUS VMB.EXE VMB.EXE should make it so. However there may be other problems.

Understatement!

Your disk will have double copies of most files in the system roots. This is a BIG problem.

The boot block won't be in the right place. This is a BIGGER problem.

Bottom line is a non-image backup of a system disk is only useful for restoring individual files. There is no simple means to convert such a disk to be bootable. That's why IMAGE backups were invented!

From where you are, really the only practical way to recover is to do a clean install of OpenVMS to a new disk, then install any required layered products. Finally copy the "personality" files from the backup into the correct locations on the new disk (make sure to get things like SYSUAF into the SYS$COMMON root). This is not as hard as it sounds, as there probably aren't a huge number of files involved. Take a DIRECTORY/DATE=MOD of the entire disk. From this you should be able to work out the most recent installation/update time. Look for files modified since that time.

In future please make sure you make useable backups of your system disk!

[Willem Grooters · Accepted solution]

I completely agree. You _could_ but it's HUGh task - error prone and not guaranteed at all to work. Check the next sequence - it might well be faster to re-create the systemsdisk from scratch (you' ll probably end up to that anyway):

1. Create a new disk
2. Copy everyting but exclude SYSn directory trees. You'll have all files then (hopefully...)
3. Create [SYSn] directory trees, do NOT! copy files - yet.
4. For all files in the [VMS$COMMON] tree, SET FILE/ENTER them into [SYSn...]. and there are a lot of them...
5. Next, check again your original disk and copy files that appear to be missing.
5. run WRITEBOOT.
6. Shutdown the system.
7. Cross your fingers and boot from that disk.
8. Very likely: big sigh and restart rebuilding a system disk. From scratch....

[Willem Grooters]

Forgot point 9 and on:
9. shutdown your system and boot from CD (standalone)
10. BACKUP/IMAGE
11. Reboot your machine.

Best you take all system specific files OFF the system disk befor you do this, and back them up regularly. Configure your system to use these files, and then make your backup copy as described above. If you have to rely on your backup, you just have to boot from it.
(Suggestion: once you created your backup disk, you can back it up as well (backup/image or by creating a shadowset with a new disk). In that case, you'll always have a copy, even if you need to boot from that primary copy)