If you already have the SAN switches and most of the servers are attached 
to the SAN it will bring the costs down (since you already spend the money)

We also use BlackDiamond and Silkworm 2800

We don't have Unix and we use 9940 and not LTO, but that should not make 
the big difference.

We don't have SSO in production at the moment but thinking about it (we 
have the hardware and the licenses already)

Best info I have about SSO I have from our StorageTek SE's, but there is 
also info at Veritas. Your Veritas rep. should also be able to help you.

Basicly what you do is two things, a media server on the servers you want 
to "direct" attach to tape drives, and then use SSO to share the drives. I 
hope your LTO's are native FC because I think that some people have had 
problems sharing the SCSI models over a SCSI/FC converter, but I don't know 
that part.

In our installation the big drawback on using SSO is that we have a lot of 
servers but not so many drives and since only one media server can use a 
given tapedrive at a time all multiplexing must be done on the media server 
that currently is using the drive(s).
This is not so much a technical problem as a planning problem, but most of 
our backups are sloow compared to the 30 MB/s native speed on the 9940's.

/johnny

At 23:46 17-12-2002 -0800, Chip Paswater wrote:
> > You could always use an ethernet port for each server like just having a
> > "cross-over" cable connectiong each other server to your media server. 
> It's
> > not easy to get it to work right, but it's basicly having a lan for 
> backups
> > to each server.
>
>This idea is interesting, but not scalable.  If I direct attach ethernet
>cards to my backup server, I'll run out of I/O slots too quickly.
>Don't think it would work for me.
>
> > The more "right" way could be to use SSO having a FC connection from each
> > server to your SAN switches going to your tape drives.
> > That should solve the performance problem but it comes at a price.
>
>This is more likely, considering most of the hosts I want to backup are
>also SAN attached.  I'm unfamiliar with SSO (which I assume is
>Shared Storage Option).  Where can I find more information on it's
>functionality?
>
> > What Extreme switch and  (if any) SAN switches are your using?
>
>Our data center core uses Extreme Black Diamond ethernet switches.  My
>SAN switches comprise of Brocade Silkworm 2800's (1gb, of course).
>
>HBA's are all emulex lp8000 and lp9000's of various bus types.
>
>We also have an EMC symmetrix, where most of the data to be backed up sits.
>
>I guess I'm basically looking for advice on how people would backup an
>envirnment such as this.  I'm a SAN/Unix geek.  Backup design is a new
>concept for me.