thanks for the fast response.

the os will be 2008r2. i was under the impression that sas performs better than scsi. we need to pull these files off the server as fast as possible as well as save as fast as possible.

i suspose what i'm asking is:

1. is raid 10 the right way to go as opposed to our current raid5?

2. can the drives keep up with the network or vice versa if i bond the nics?

3. and where will the bottleneck occur?

Your "SAS" drives are really just SATA drives with SAS controllers (PCB) on it. This means that the performance will be that of a SATA drive.

Unless you carve the 4-disk raid 10 into 2 virtual disks (preventing you from ever growing the raid set), you'll need to change the bios to UEFI. For that you'll need 2008 x64, 2008 R2 (always x64), RHEL6 or a different OS that supports UEFI boot (excludes 32-bit Windows versions and 2003 and older, but also excludes RHEL4 and RHEL5).

NIC teaming will give more bandwidth. However, depending on how you set up your NIC team, your ethernet switches may need to be configured for this NIC team.

SAS does perform better than SCSI, but 2TB drives aren't 10k or 15k rpm; they are just 7200rpm. These drives are considered Nearline SAS. This means that are the same internally as a (7200rpm) SATA drive, except that the little PCB on the side of the drive is a SAS controller card. So they are as fast as a SATA drive basically.

If you want about 4TB usable space with good performance, I would suggest to start with figuring out if what your read/write ratio is. If 30% or more is writes, you want to use raid 10. If less than 30% is writes, raid 5 should yield acceptable performance. Once you determine that, shop for 600GB 15k rpm SAS drives. You'll need 14 of them if you want to use raid 10 or 8 of them if you want to use raid 5 (not counting hotspares on either of these 2).

After you get the drive and raid part figured out, you could either team the 4 NICs and create a LAG on your switch to accommodate this team, or better yet just add a single or dual port 10Gbit NIC and either buy a switch with 1 or 2 10Gbit ports or if you already have such a switch, plug these NICs into those ports. You can team those 2 NICs and even w/o a LAG you should have a lot more bandwidth than even the 4 onboard NICs can offer.

ah....

thanks for that. I should have done my reading. We've now changed to  4x 600gb 15k sas and going for a raid 10.

10Gbit is a step too far at this point as we don't have the switches to support. We do however have the spare ports to team all 4 ports on the server together but would we need it?

Would 2 x 1Gbit using jumbo frames be able to support the write/read to hard drives or vice versa? Where would the bottleneck be here?
If so, i'd rather use the other spare ports for a backup server on another subnet.

Lots of questions I know, but we want to get this purchase right as we see this server doing us for another 5 years.

l