> > So the connection from the Server to the library is not the bottleneck. I
> > have 4 drives going down 1 fibre path and 4 down the other. Considering
> > 1gb FC can do 100MB/sec, and an LTO drive does 15MB/sec, that means a max
> > througput of 60MB/sec per FC port.
>
> Minor correction: that's the uncompressed speed. If you're doing
> compression on your drives, which you should be, you could theoretically
> push that up to 120mB/sec. Realistically I've seen LTO drives hit
> 20mB/sec each. Also, the SBUS cards on the E4000's aren't known for the
> best throughput so they could be part of your problem.
Should I turn on compression in Veritas as well as using drive compression?
Or should I use one or the other. If so, which one? I would assume drive
compression only, but wouldn't compression from within Netbackup give me
compression over my already taxed ethernet link?
> > So how do I scale the solution to open the ethernet bottleneck? Veritas is
> > not being forthcoming with a solution, and I can't seem to find any best
> > practices documents on their site with any insight.
>
> This is just the sort of thing SSO was designed to handle. You don't have
> to put all of your large servers on the SAN and make them media servers as
> long as they're all served by gigabit ethernet. You could pick another
> machine or two to make media servers or, if you want to keep the load off
> of your production machines, buy a new box just for this purpose. Each
> tape drive can only talk to one media server at a time, but if your
> master/media is backing up 5 hosts, your new media server could be backing
> up 5 more or whatever.
> If you have any specific questions let me know. I work for a storage
> integrator/reseller so this is what I do for a living. I've seen quite a
> number of installations where the LTO drives are not native fiber and they
> work quite well. Until about eight or ten months ago LTO and fiber were a
> bad combination due to instability, lack of interoperability, etc , but it
> has come a long way since then. Our LTO installs are rock solid even with
> fiber/SCSI bridges.
Thanks Jason, this makes perfect sense. Sounds like what I need to do is
let the e4000 drive 4 of the drives, and go out and buy a couple of dual
proc e220's to drive the other 4 drives. These e220's would use the SSO
drives but the e4000 would control the robot for all 8 drives.
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