[Mimedefang] Re: Disk imaging software

[Kevin A. McGrail]

There is no imaging of a live system over a network that will really achieve
what you want.  Assuming you can take down the system, your choices are:

-- Down the box and run ghost.  It works for ext2/ext3 quite well.  I use
the Corp Edition.  If you use Ghost, make DAMN sure you have a boot floppy
for the system because 99.9% of the time I have had to run lilo -v or
grub-install on the system to reinit the boot block correctly for Linux.

-- Use Tar in Single Mode. Here's some hints about tar that I've found over
the years.

Run the box in single mode (/etc/rc.d/init.d/single if you have RH or
similar)
tar the box up excluding usually /mnt and /proc (mnt because you can get
loops and proc because /proc is a symlink to stuff in memory)
COPY the passwd and group file

If you need to restore, book a restore installation CD / Parallel drive,
whatever.

mkdir proc (it's a link that there is a mount in the kernel)
mkdir etc
mkdir mnt and any subdirs you had in mnt
chown/grp/mod those dirs as before

put group and passwd in etc
chown/grp/mod those files as before

Set a blank umask
umask 0000

Untar the system.

If you don't do the umask and the group stuff, you might end up with files
with wrong perms and ownership.

Both of these are VERY slow methods so if you can limit the backups to
non-data files, it will help.  We tar up about 32GBs on our main server
every evening using bzip compression on a dual 2.4GHz system putting the tar
on a seperate HD and that takes about 6.5 hours.

Regards,
KAM

> > tar and a Linux rescue disk is the no-frills recommended way to do it...
> You
> > can, at least use just about any version of Linux rescue disk (it does
> NOT
> > have to match the release you are running on the system), so pick a
> recent
> > release that has the Broadcom drivers built-in. :-(
>
> Did I mention I need to do this across a network connection?  I don't have
> a local tape drive.
>
> I will look into this solution using an NFS mounted file system to store
> the tar file one.