Hello,
We have been struggling to get a good cloning plan going for the VTL,
there were additional challenges.
1. We chose to do Automatic cloning
--Groups don't end in time, delaying cloning.
2. Stuck groups
----Delays cloning, restarts, incomplete clones--bunch of headaches, i
would prefer dualcopy when and if networker will support it.
3. Takes some scripting capability to check on failed clones, prepare
tapes for offsite and process clone\failures.
----More headaches.
4. Device management with VTL & Physical
--- Not easy, more the storagenodes more complex, jbconfig blues, wizard
has some capability however, device and tape management remains a big
challenge and will only get worse with addition of VTL.
---Tapes on VTL often go out of sync, reloading of drivers could
potentially through off tape order, constant reconfigurations destabilize
the environment, granted keeping it simple is the way to go, keep the
devices, pools, schedules and sn to the minimum.
5. Dedupe and VTL
--- Unable to predict and have any control over what exactly the dedupe
will do and what might be the VTL capacity, Tape size issues, major
problems managing tapes in VTL in relationship to sizing.
6.Cloning
---Unpredictable at best, often, missing tape schedules due to slow
clients, Tape and backup failures, re-tries and performance, reality check
and keeping the architecture simple with cloning limits to particular
groups, separations on test and production etc would help, scripting
knowledge would come in handy.
----Have a test server and plan out your scripts, groups, pools etc before
implementing in production to limit unknowns.
----Limit what needs to be cloned, NDMP cloning seems to be more
problematic then others, you may need additional physical devices, time
and testing before it's ready for prime time. ( One that we have issues
with are on Networker 7.3.3, Netapp filer Fas3050, NDMP V-4), typically
hung clones, incorrect completion notices etc via networker.
---My preference would be to generate saveset list and use external
scheduler for cloning for better control over the cloning environment.
---Clients may need to be stopped at a predetermined time to allow cloning
to resume ( in auto clone environment), leaving you with additional
failures, incomplete cloning to worry about.
7. VTL itself
--Superfast restores
--Ability to keep data onsite for quick restores for longer period of
times.
---Ability to partition the Lib and attach multiple library to multiple
servers, SN and even different backup types.
---Dedup for what it's worth.
---Apparently, fewer Tape issues.
---Ability to create multiple drives and assign to different hosts
--- Will need considerable SAN and Zoning knowledge.
I am sure there are workarounds and some backup admins may have perfected
the techniques more then others but for most others the challenges are
real & difficult to deal with.Before venturing out to the VTL world make
sure you have done your homework.
HTH
To sign off this list, send email to listserv AT listserv.temple DOT edu and
type "signoff networker" in the body of the email. Please write to
networker-request AT listserv.temple DOT edu if you have any problems with this
list. You can access the archives at
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER
|
