Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Just purchased a "fully functional" PowerEdge 2850 server on Ebay, but, it arrived without any drives! So much for "fully functional"!

Anyway, I have drives arriving today. I only have 4 caddies, but, I noticed that there is only a cable attached to Channel A of the SCSI back plane.

I am a server newbie, and have bought this unit to learn and "cut my teeth" on server's and server OS's. Can I utilize all 6 drive slots with only this Channel A cable attached or do I need to purchase a Channel B cable?

If I do not need the "B" what is this for? The optional tape drive? At first I wondered if maybe the slots were staggered 0, 1, 3 on Channel A and 2, 4, 6 on B, but, I am not really sure.

Anyway, I appreciate the help.

share|improve this question

You put appropriate-type drives in the caddies, and insert them into the system.

It's been a while since I've been inside a 2850, but as I recall you can use all six slots on the backplane with only "Channel A" in a normal configuration.

The 2850 can also be operated with a "split backplane", but that requires additional hardware, and I've never seen a machine configured that way in the wild (presumably it would be useful if your main hard drives were saturating the controller and you needed to milk the maximum possible performance from the disk subsystem).

For more information on the PowerEdge 2850 series you should really be referring to Dell's documentation.
As the system manufacturer, they're more likely to have correct and up-to-date information than anyone else, and they should be your first stop when you have a question about your system...

share|improve this answer
Thanks! I found out by experience that Channel A is for RAID and Channel B Non-RAID......(I had removed the Riser Card to re-seat the RAID DIMM which required removal of the RAID battery first. I accidentally plugged the SCSI cable back in to Channel B and found my RAID non-functional.... – user173115 May 10 '13 at 13:55

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.