SDLT versus LTO tape backup - VMS
This is a discussion on SDLT versus LTO tape backup - VMS ; I have been a happy user of DLT/SDLT tapes for many years.
One of my sites is currently using SDLT 160/320, but the
backups are now taking two tapes and they want to upgrade.
The next logical step up is ...
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SDLT versus LTO tape backup
I have been a happy user of DLT/SDLT tapes for many years.
One of my sites is currently using SDLT 160/320, but the
backups are now taking two tapes and they want to upgrade.
The next logical step up is SDLT 300/600 (SDLT-II tapes),
but I want to consider other options. One option is the
LTO-3 (400 GB / 800 GB) drive.
I would to know your opinions on these two options, plus
any others you might be using. I hear some people saying
that SDLT is dead and the future is LTO, but other disagree.
What do *YOU* use for your most valuable data, and why?
Thanks,
Alan Frisbie
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Re: SDLT versus LTO tape backup
Alan Frisbie wrote on 11/09/2008 :
> I have been a happy user of DLT/SDLT tapes for many years.
> One of my sites is currently using SDLT 160/320, but the
> backups are now taking two tapes and they want to upgrade.
>
> The next logical step up is SDLT 300/600 (SDLT-II tapes),
> but I want to consider other options. One option is the
> LTO-3 (400 GB / 800 GB) drive.
>
> I would to know your opinions on these two options, plus
> any others you might be using. I hear some people saying
> that SDLT is dead and the future is LTO, but other disagree.
>
> What do *YOU* use for your most valuable data, and why?
>
> Thanks,
> Alan Frisbie
SUN (ex-STK) 9840 and 9940 fibre-channel tape drives. Expensive
(List price > 30k¤) but unbeatable in performance & reliability.
We have a pool of 40 drives that we use from OpenVMS, NSK, HP-UX,
Solaris, Tru64, Red Hat, and Windows.
--
Marc Van Dyck
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Re: SDLT versus LTO tape backup
Hi Alan,
Alan Frisbie wrote:
> I have been a happy user of DLT/SDLT tapes for many years.
> One of my sites is currently using SDLT 160/320, but the
> backups are now taking two tapes and they want to upgrade.
>
> The next logical step up is SDLT 300/600 (SDLT-II tapes),
> but I want to consider other options. One option is the
> LTO-3 (400 GB / 800 GB) drive.
>
> I would to know your opinions on these two options, plus
> any others you might be using. I hear some people saying
> that SDLT is dead and the future is LTO, but other disagree.
>
> What do *YOU* use for your most valuable data, and why?
Like you, for a long time the systems I manage have been using DLT-IV media.
A couple of years ago two systems acquired DLT-VS80 drives which are
horrible (very slow). The most recent systems are using LTO-2 and it's very
quick with high capacity too.
When I look at HP's web site I very much get the impression that (S)DLT is
on the decline -- but that might just be HP's business decision for their
server lines.
Of course if you change from SDLT-xxx to LTO-xxx you have to retain the old
hardware to read the old tapes, or rewrite all your tapes onto the new
media. So far I've favoured the former approach. It's generally useful to
have a choice of media availble for when someone sends you something unexpected!
Regards,
Jeremy Begg
jeremy at vsm com au
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Re: SDLT versus LTO tape backup
In article , Alan Frisbie writes:
> I have been a happy user of DLT/SDLT tapes for many years.
> One of my sites is currently using SDLT 160/320, but the
> backups are now taking two tapes and they want to upgrade.
>
> The next logical step up is SDLT 300/600 (SDLT-II tapes),
> but I want to consider other options. One option is the
> LTO-3 (400 GB / 800 GB) drive.
>
> I would to know your opinions on these two options, plus
> any others you might be using. I hear some people saying
> that SDLT is dead and the future is LTO, but other disagree.
[...]
We use an Overland robotic with 24 SDLT 160/320 tapes and two SDLT drives. Runs
very well. But you need a software to drive the thing, and it's rather
expensive. (the server is under Solaris, not VMS sorry ...).
LTO-3 is rather tempting, the storage capacity is now better than DSLT one.
Patrick
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Re: SDLT versus LTO tape backup
On Sep 11, 8:02*pm, Alan Frisbie
wrote:
> I have been a happy user of DLT/SDLT tapes for many years.
> One of my sites is currently using SDLT 160/320, but the
> backups are now taking two tapes and they want to upgrade.
>
> The next logical step up is SDLT 300/600 (SDLT-II tapes),
> but I want to consider other options. * One option is the
> LTO-3 (400 GB / 800 GB) drive.
>
> I would to know your opinions on these two options, plus
> any others you might be using. * I hear some people saying
> that SDLT is dead and the future is LTO, but other disagree.
>
> What do *YOU* use for your most valuable data, and why?
>
> Thanks,
> Alan Frisbie
We went from DLT4 to SDLT to LTO3. LTO3 has certainly been the most
stable, with only one drive swap so far. You can also mix SDLT and LTO
in a MSL6000 library, although I believe LTO3 will also read-only
SDLT. Please check these facts on the HP support matrix.
One thing you should bear in mind is if you don't feed the LTO drive
quickly enough, you may see porrer performance than the SDLT. We
upgraded from a HSG SAN to an EVA8000, so there are no data
bottlenecks anywhere.
Rob.
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Re: SDLT versus LTO tape backup
In article , Alan Frisbie writes:
> I have been a happy user of DLT/SDLT tapes for many years.
> One of my sites is currently using SDLT 160/320, but the
> backups are now taking two tapes and they want to upgrade.
>
> The next logical step up is SDLT 300/600 (SDLT-II tapes),
> but I want to consider other options. One option is the
> LTO-3 (400 GB / 800 GB) drive.
>
> I would to know your opinions on these two options, plus
> any others you might be using. I hear some people saying
> that SDLT is dead and the future is LTO, but other disagree.
>
> What do *YOU* use for your most valuable data, and why?
4mm DDS-1. I know some people have had problems with DDS, but
I haven't. ANd if it takes two tapes, then I load a second tape.
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Re: SDLT versus LTO tape backup
For those that may not have run into this writeup on DLT:
http://en.wikipedia.org/wiki/Digital_Linear_Tape
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Re: SDLT versus LTO tape backup
On Sep 12, 10:07*am, DaveG wrote:
> For those that may not have run into this writeup on DLT:
>
> http://en.wikipedia.org/wiki/Digital_Linear_Tape
I switched from DLT4 to LTO3 about 3 months ago, and the performance
is great. Backup times were reduced by 50%. Only bad comment is
that we have had an issue with the loader being unable to extract a
tape cassette from a given slot and load it into a drive. HP says
it is a known problem however thsy are unable to offer any real
solution except to "exercise" the cassettes manually, (i.e. insert and
remove the cassette a few times) before finally inserting it into the
library.
Although it seems cluedgy, since we started doing this we have had no
reoccurrence of the problem (touch wood), which previously was
happening approximately once each week, and coincidentally, always in
the same slot (although we don't use that many of our slots).
Finally, it seems that the exercising doesnt necessarily have to be
done in the slot the tape is destined for, it can be done in the mail
slot. Even if it is subsequently move to an internal slot, the
problem doesn't seem to occur after applying the HP solution.
Dave
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Re: SDLT versus LTO tape backup
Rob wrote:
> On Sep 11, 8:02??pm, Alan Frisbie
> wrote:
> > I have been a happy user of DLT/SDLT tapes for many years.
> > One of my sites is currently using SDLT 160/320, but the
> > backups are now taking two tapes and they want to upgrade.
> >
> > The next logical step up is SDLT 300/600 (SDLT-II tapes),
> > but I want to consider other options. ?? One option is the
> > LTO-3 (400 GB / 800 GB) drive.
> >
> > I would to know your opinions on these two options, plus
> > any others you might be using. ?? I hear some people saying
> > that SDLT is dead and the future is LTO, but other disagree.
> >
> > What do *YOU* use for your most valuable data, and why?
> >
> > Thanks,
> > Alan Frisbie
> We went from DLT4 to SDLT to LTO3. LTO3 has certainly been the most
> stable, with only one drive swap so far. You can also mix SDLT and LTO
> in a MSL6000 library, although I believe LTO3 will also read-only
> SDLT. Please check these facts on the HP support matrix.
I was looking into mixing SDLT and LTO and the document I found
said the following about mixing SDLT and LTO in the MSL6000 (and
MSL5000 as well):
MSL libraries will not support SDLT and Ultrium cartridges in the same
library module because of differences in media magazine size. However,
support for MSL libraries with SDLT and Ultrium drives in separate
modules in a multi-unit stack is supported.
I found the documentation here:
http://h18006.www1.hp.com/products/s...atibility.html
The specific document was:
ftp://ftp.compaq.com/pub/products/st...c/tapestorage/
SW_MSL_Tape_Auto_bc_FINAL.hires_040808.pdf
(that URL is split)
Which was linked from "Tape compatibility" -> "Business class libraries
drive upgrade matrix".
--
Eric Dittman
dittman@dittman.net
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Re: SDLT versus LTO tape backup
Any experience / comments re HP StorageWorks 1/8 G2 LTO-4 Ultrium 1760
SCSI Tape Autoloader
AJ816A?
Thanks,
Carl Friedberg
carl@nospamcomets.com
On Sun, Sep 14, 2008 at 4:26 PM, wrote:
> Rob wrote:
>> On Sep 11, 8:02??pm, Alan Frisbie
>> wrote:
>> > I have been a happy user of DLT/SDLT tapes for many years.
>> > One of my sites is currently using SDLT 160/320, but the
>> > backups are now taking two tapes and they want to upgrade.
>> >
>> > The next logical step up is SDLT 300/600 (SDLT-II tapes),
>> > but I want to consider other options. ?? One option is the
>> > LTO-3 (400 GB / 800 GB) drive.
>> >
>> > I would to know your opinions on these two options, plus
>> > any others you might be using. ?? I hear some people saying
>> > that SDLT is dead and the future is LTO, but other disagree.
>> >
>> > What do *YOU* use for your most valuable data, and why?
>> >
>> > Thanks,
>> > Alan Frisbie
>
>> We went from DLT4 to SDLT to LTO3. LTO3 has certainly been the most
>> stable, with only one drive swap so far. You can also mix SDLT and LTO
>> in a MSL6000 library, although I believe LTO3 will also read-only
>> SDLT. Please check these facts on the HP support matrix.
>
> I was looking into mixing SDLT and LTO and the document I found
> said the following about mixing SDLT and LTO in the MSL6000 (and
> MSL5000 as well):
>
> MSL libraries will not support SDLT and Ultrium cartridges in the same
> library module because of differences in media magazine size. However,
> support for MSL libraries with SDLT and Ultrium drives in separate
> modules in a multi-unit stack is supported.
>
> I found the documentation here:
>
> http://h18006.www1.hp.com/products/s...atibility.html
>
> The specific document was:
>
> ftp://ftp.compaq.com/pub/products/st...c/tapestorage/
> SW_MSL_Tape_Auto_bc_FINAL.hires_040808.pdf
> (that URL is split)
>
> Which was linked from "Tape compatibility" -> "Business class libraries
> drive upgrade matrix".
> --
> Eric Dittman
> dittman@dittman.net
>