Jon wrote:
 
>Now, we realized we own some older equiptment that we dont want
>anymore and are considering trading the old equiptment for 2 or 4 more f/w
>4GB drives - obviously, to add ot the mirrored array. This would give us a
>maximum of 5 devices on each of our two f/w channels. Suddenly, our SSE
>claims that HP does not recommend more than *3* devices on a f/w channel -
>or shazam! there goes our performance. Does anyone have any insight on this?
 
There is no problem to put 5 devices on a f/w channel.  In fact, you don't
have to worry about the channel issue until you reach 9 or so.
 
However, I do concern that if you have enough disks to handle the I/O load!
Even though currently you have 6 disks for you production data, you really
just have 3 disks to spread the I/O load (since they are mirrored).  Make
sure all performance critical data are evenly spread across all disks.
 
If you know your average and peak I/O rate, you can figure out how many
disks are needed to support the demand.  3 sounds tight, I would feel more
comfortable with 5.  Good luck.
 
Paul Wang                          phone: (408) 988-7378
SolutionSoft Systems, Inc.         fax  : (408) 988-4777
                                   email: [log in to unmask]