I don't remember the link, but IBM has a "white paper" about this.
LTO is not 3590 (or 9840 and 9940) class, and it will never be.

Tech. specs is something that you can read like someone reads the bibel.

What I think is interesting is: How does it work in real life.

If what you do is a lot of very large backups LTO is fine. But a little 
like DLT start and stop is very bad for performance.
9840B by the way has a lot better specs then LTO. 20 MB/s and up to 1:4 
compression. If I remember LTO right is says 15MB/s and 1:2 compression.
But I have seen people running 35MB/s on 9840A on Solaris and using 
NetBackup 3.4.
9940B should be out around 1. sep. this year. They will also have 20MB/s 
and 1:4 compression and 200GB native.

If we talk about StorageTek (I know them better then IBM these days) you 
can't compare 9840 to LTO when we talk about how much data you can have. 
9840 is made for fast mount time and fast search time.
Compare 9940 to LTO. 9940A had 60GB native and around 120-180 GB compressed 
in our installation.
When we will change to 9940B later this year we will have 400-600GB compressed.

But don't let the specs blind you. There is a lot more to tapedrives and 
backups that people tend to know and remember.

We spend 4-5 times longer to calculate what drives to use then what 
disksubsystem to use in our SAN.

/johnny

At 11:20 13-06-2002 -0700, Geoffrey Hazel wrote:

>Why do you say LTO is a downgrade from 9840?  From what I've been told, it
>has faster data transfer and the tapes hold 5x as much data... what's the
>downside?
>
>
>
> 
>
>                       Johnny 
>
>                       Oestergaard              To:       Geoffrey 
> Hazel/Seattle/Contr/IBM@IBMUS, 
> Veritas-bu AT mailman.eng.auburn DOT edu
>                       <joe AT joe DOT net>            cc: 
>
>                                                Subject:  Re: [Veritas-bu] 
> Multiple SSO servers on 1 master server
>                       06/13/02 10:59 
> AM 
>
> 
>
> 
>
>
>
>
>Not that I know anything about your problem, except that using more media
>servers over SSO should not be a problem.
>
>But what I was thinking when I read your email was:
>
>Woww. Downgrading from 9840 to LTO that is something.
>If I was you I would look into 9940 and not LTO. LTO is not even close to
>STK9840, STK9940 and IBM 3590
>
>/johnny
>
>
>At 09:17 12-06-2002 -0700, Geoffrey Hazel wrote:
> >We have an SSO setup with 4 media servers and 1 master/media server going
> >to a STK Powderhorn with 20 9840 drives.  We are going to be replacing
>that
> >Powderhorn with an L700 with LTO tapes and drives, also intended to be an
> >SSO setkup.
> >
> >Now, when I defined 1 tape drive (shared) on my master server (only), we
> >could no longer seee the 9840 drives in vmdareq!  But as soon as the new
> >drive was removed, voila, the 9840 drives reappeard.
> >
> >A Vertias consultant on site theorized that you could only have one SSO
> >robot on a master server.   So does anyone know if this is true or not?
>If
> >it is true, then we're going to need a plan for doing a hard cutover
> >between the two robots, but if not, then we wonder why the drive
>wierdness.
> >
> >
> >
> >
> >_______________________________________________
> >Veritas-bu maillist  -  Veritas-bu AT mailman.eng.auburn DOT edu
> >http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu