Annoyingly, you can't write direct from the mksysb command like you can with tape and the write might take 3 hours by the way. There is time and space taken to manipulate the mksysb image file ready for the write (25 minutes maybe) but the write to real media is slow.

If your mksysb image file is about 2Gb (must fit a single DVD I think) then you will need 5Gb free in rootvg so it can build /mkcd/cd_fs and /mkcd/cd_images at an appropriate size (determined for you in the mkdvd script)


Before you create your mksysb image, make sure you save an structural image of any volume groups you want to rebuild too like this:-

Code:

rm -r /tmp/vgdata                          # Clear out any old definitions
mkszfile                                   # Create rootvg requirements
for vg in `lsvg|sort|grep -v rootvg`
do
   echo "^\\\./" > /etc/exclude.$vg        # Exclude all files, i.e. take just the structure
   savevg -ef /disaster/$vg.structure $vg
done

# Now run mksysb as you normally would to a file
# Then run mkdvd to write to media

If the directory /disaster is in the rootvg then these will be available on the recovery. You can use:-

Code:

restvg -qf /disaster/vg-name.structure hdisk2 hdisk3 hdisk4....

This will build your replacement volume groups to match the sizes you had at the time. It will restore (and mount) filesystems and raw logical volumes and then you can recover your business data from whatever other backup solution you have.

It is less error prone and far quicker that having a scripted mkvg-mklv-crfs. On a recovery where we stopped issuing all the makes & creates and used restvg instead, we saved 4 hours just on the step to recreate the disk layout.



Robin