I can't agree with the statement "Do a disaster recovery?  Then you never
need images, only incremental backups."

That is EXACTLY why we need to do IMAGE backups.

When our mail systems disk array died, it took >15 DAYS to restore
>15MILLION individual files. The slowness was due to OS overhead trying to
restore/register that many files. TSM was constantly idle/waiting.   Total
storage was only 400GB. If we would have had an IMAGE backup to restore
the affected filesystem and then did incremental restore from that point,
we feel the recovery would have been considerably shorter !




Stef Coene <stef.coene AT DOCUM DOT ORG>
Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
10/26/2004 03:13 PM
Please respond to
"ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>


To
ADSM-L AT VM.MARIST DOT EDU
cc

Subject
Re: Open file and image backups on Linux






On Tuesday 26 October 2004 19:37, Sandra wrote:
> Dear Mark,
> I am confused again.
Me too :)

> See, I need to take backup (image or incremental) of entire system.
> IMAGETYPE is one things, and running fsck later on after restore is
> another.
Why?  What do you want to do?  Do a disaster recovery?  Then you never
need
images, only incremental backups.

> Now question is, BMR is actually something, that will backup and then
> restore the entire system in one go. Image is the solution for this
> probably.
>
> Now, If i take Image backup and my machine crashes, all i need to do is
to
> install my OS and BA client, and start the restore of the image of all
the
> file systems (including system file system). This way when i am going to
> restart after this, i will be on the same level as the image was, onlly
> thing that i would do is to run fsck if there is any problem.
My DR scenario:
- AIX: mksysb rules :)).  Mksysb is a bootable tape (or cd, dvd, or
network)
that restores a single AIX server in 1 go.  I did a test restore of a
cluster
node with TSM and domino and after 45 min the minutes was up and running
!!!
I started HACMP and TSM and domino were up and running without any
problems.
Use mksysb on a local tape for the TSM server (+ TSM db backup to disk ona

filesystem in rootvg) and nim (network mksysb) for the AIX clients.

- Windows: CBMR is cool.  I used CBMR to restore a TSM server and it woked

flawless.  This was on a local, single, dedicated lto tape.  CBMR is also
network aware so you can backup over the network directly to a TSM server.

If you don't use CBMR, you have to do it manually as described in the
docs.
Or ASR, available in 2003 and XP.  With ASR, you can boot from a CD
(windows +
TSM client) and recover everything directly from the TSM server.

- Linux: I never tried it, but there are a lot of tricks you can use.  I
should install a basic linux in a partition, recreate the original
partition,
mounts them and restore everything.  You can boot from cd or change the
bootloader to load the fresh restored linux.
I know Cristie was working on a linux version of the CBMR software, but I
don't know if it's finished.

> IMPORTANT: when i will initiate the image backup, the only thing that
would
> be running would be those OS files and no application other than that.
If
> there is some system file that is open in for exampple in /usr, and
there
> is no application that is using that file, then it will be backed up??
Am i
> right?
Yes, with *unix you can backup any file you want, even open files.  But
the
backup may be inconsistent.  It also depends if the file is open read-only
of
read-write and if it's changed or not.  Also, TSM will try by default 3
times
to backup a changed file.
So, unless you have a database running, only log files are changed.  And
you
don't care about log files, they will not prevent you from doing a
disaster
restore.

> I m using Linux................... !!!!!!!!!!!!!!!!!!!!!!!!
Good choice :)

Stef


--
stef.coene AT docum DOT org
 "Using Linux as bandwidth manager"
     http://www.docum.org/