Yes, we have some luxeries others don't.
Our MAN/WAN is sufficent with dark fiber to back up cross site, so in the
nature of the backup its offsite as soon as its complete. Since tape needs a
copy in the advent of media failure we zone our fabric so the TSM server tape
libraries have a couple of tape drives at the source site. We keep our
primary copy offsite and our copypool on site ... If you can afford it, it is
cool. We also mirror our tsm server luns between sites, so in the case of the
worst we can import the volume groups and bring up a second instance. We
didn't have the emc mirrorview at the time and gave aix mirroring a try between
the different storage platforms. Things have been good.
>>> Wanda.Prather AT JHUAPL DOT EDU 09/01/06 10:21AM >>>
Hi Eric,
In a disaster, you mark your primary pool volumes "destroyed", but they
are still in your DB, along with all the appropriate file entries.
If you start backing up again, TSM just continues doing incrementals,
because the DB tells it the older files were already backed up.
To rebuild your primary pool, you can do RESTORE STGPOOL; TSM will mount
the copy pool tapes and start rebuilding the primary pool.
As each of the primary volumes gets completely rebuilt, TSM will delete
the old entry from the DB.
In the meantime, anytime somebody tries to do a RESTORE, TSM sees the
primary tape is marked DESTROYED, and automatically requests the mount
from the copy pool tape.
So I don't see the which-is-primary-which-is-copypool question to be an
issue. (You have to eventually make a 2nd copy of all the data again,
regardless).
With the advent of practical long-distance fibre and/or FCIP, several of
my customers already have implemented or are considering installing a
2nd library in the twin center and making the copy pool tapes there
directly, instead of just sending the tapes there by courier and having
them sit in a box. That's the ideal situation. You pre-install TSM on
one of the servers in the twin center (but leave it shut down); make
sure your PREPARE script also gets made to a disk in the twin center.
Then when you have your disaster, all you have to do is restore the TSM
DB, and you're ready to start restoring your clients.
An even better idea is putting the PRIMARY pool at the twin center, and
the COPY pool at your main center. That way in a disaster that hits
your clients, your TSM server is unaffected; you're ready to do restores
as soon as they give you something to restore to, and you have all your
DRIVES available.
A VTL at the remote site is also a great idea; because your restores
aren't limited then by the number of tape drives; just your bandwidth.
If you don't have a library at your twin center, you can have a couple
of manual drives there. There is no requirement for TSM to have a
library, or the same type of library. BUT, if you don't have a library,
you certainly won't be doing restores very quickly for your clients.
So it depends on what your management thinks considers their TIME
requirement to be in a disaster recovery-situation. You can be sitting
at the twin site with a box of tapes waiting for them to buy you some
hardware, or you can be ready to restore in 5 minutes - just a matter of
the $ they are willing to spend...
Wanda
-----Original Message-----
From: ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU] On Behalf Of
Loon, E.J. van - SPLXM
Sent: Friday, September 01, 2006 7:17 AM
To: ADSM-L AT VM.MARIST DOT EDU
Subject: Making TSM twin-center compliant
Hi *SM-ers!
We are about to implement a second (fallback) IT center on another
location. The idea is to create a hot standby environment for TSM.
We are already using a separate copypool which will be moved to the new
remote location, so if the primary pool gets lost, we have all data (up
until the last backup stgpool of course) on the remote location.
However, in case of a disaster, not only will we have to be able to
recover clients (from this copypool), but we also need to continue
backup here.
This would be no problem if one could promote a TSM copypool to a
primary pool. In this case one could just continue making (the forever
incremental) backups, but TSM doesn't offer this function (yet). An
UPDATE COPYPOOL POOLTYPE=PRIMARY would be very nice to have...
The only thing I could think of is creating a standby library which can
be connected in case of a disaster to host the new primary pool and
start all over with backing up. A waste of money because it will
probably (and hopefully) never be used..
How do other twin-centers solve this?
Thank you very much for any hints and tips in advance!!!
Kindest regards,
Eric van Loon
KLM Royal Dutch Airlines
**********************************************************************
For information, services and offers, please visit our web site:
http://www.klm.com. This e-mail and any attachment may contain
confidential and privileged material intended for the addressee only. If
you are not the addressee, you are notified that no part of the e-mail
or any attachment may be disclosed, copied or distributed, and that any
other action related to this e-mail or attachment is strictly
prohibited, and may be unlawful. If you have received this e-mail by
error, please notify the sender immediately by return e-mail, and delete
this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its
subsidiaries and/or its employees shall not be liable for the incorrect
or incomplete transmission of this e-mail or any attachments, nor
responsible for any delay in receipt.
Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch
Airlines) is registered in Amstelveen, The Netherlands, with registered
number 33014286
**********************************************************************
-------------------------
CONFIDENTIALITY NOTICE: This message is confidential, intended only for the
named recipient(s) and may contain information that is privileged, or exempt
from disclosure under applicable law. If you are not the intended recipient(s),
you are notified that the dissemination, distribution or copying of this
message is strictly prohibited. If you receive this message in error, or are
not the named recipient(s), please notify the sender by reply e-mail, delete
this e-mail from your computer, and destroy any copies in any form immediately.
Receipt by anyone other than the named recipient(s) is not a waiver of any
attorney-client, work product, or other applicable privilege. This message and
all contents may be reviewed by authorized parties of the Catholic Health
System other than those named in the message header.
The contents of this message do not bind the Catholic Health System to any
contract, position, or course of action unless the sender is specifically
authorized to enter into contracts on behalf of the Catholic Health System. The
contents of this message do not necessarily constitute an official
representation of the Catholic Health System.
|
