[t2ffn]

Right, something is a miss in my server. I stripped the server as I bought a new 4in3 cage to fit, and decided to clean all of the fans, hdds etc of dust and rearrange the order of drives to something more logical.

After putting everything back together, only 9 of the 10 drives are visible on the server

I have had all of the sata and power cables out, back in in different configurations etc. I narrowed it down to which drive was not running at one point, tested it solo and its fine. Put all 10 back in, only 9 drives showing. It seems its usually one of the five 2TB drives that goes awol.

This is driving me nuts. I haven't added another drive. All I did was rearrange and remove some fans (had LEDs which I hated, replaced one with a silent fan)

I am using a Corsair TX650W PSU, which has 2x4 Sata connections, and I use a molex > 3 sata adapter for the remaining 2 drives.

I have a SAS card with breakout cables for 8 drives, and use the mobo for the boot drive and the 3TB drive, as I found it went into an endless reboot loop with the 3TB drive connected to the SAS

Any idea what might be going on? I can't seem to get all 10 up at once. I dont think its power as the PSU is strong and I haven't added another drive to use more juice.

This could take a lot of trial and error to find and correct as I use RDC to get into the server, so closing down, swapping internals, rebooting, logging in etc takes a while.

Grrrrr

[T800]

What type of server is it?
Can you add another drive to see if it is seen?
If you swap the SATA cable with a drive that doesnt appear with one that does, does the other drive dissapear and the original missing one appear?
Is it a particular port on the mobo or card that it always happens too.

[BigO]

Yeah i would try another drive or def try out some other cables as well.

Also does the BIOS see the drive? When botting up, does the SAS card register the drive as being hooked up? Can you go into the BIOS of the SAS card and see if its listed there?

Is your SAS card does not see it, your OS wont.

Also you can try to hook the drive up to the MOBO if you have some unused prots which it sounds like you might.

Also you never mention what OS your server is running which will help us give tyou some tests you can run that are more server specific.

[numb7rs]

Are you saying that the dropped drive changes? That's pretty damn weird.

I agree it's not likely to be power related, as you've only removed things, and the PSU is single rail.

It could be any number of things, you're definitely going to need some more information to solve this one. Is there no way you can view the port-by-port status of the SAS card? I think it would be worth dragging a screen and keyboard to wherever this server is, if you can.

Otherwise, I've thought of a few things you can do ...

• Test each drive and SATA cable in another machine (SATA is hot-pluggable :cool2
  
• Failing that, test each drive and SATA cable in the server, but plugged into the mobo.
  
• Run the server with one of the SAS drives unplugged (power and data). If you still get a random drive dropped, that points to a software problem in the SAS card.
  
• If you can do it without losing data, update the SAS card firmware.
  
• Restore the machine to its state when it was working, see if it works again.
  

Hopefully one of these gives you something useful.

Also, please could you list the full spec of the system (including software and any RAID config)? It might help me think of something else ...

[t2ffn]

Thanks for the posts.

Its a 'simple server' consisting of a tower with 12 drive bays, running win7. No backup software yet, no raid.

I have started doing some trial and error tonight... I unplugged the sata cables from all drives except the boot drive attached to the mobo, and one of the SAS breakout cables is hooked up to 4 drives.

On booting into the bios, all 5 drives are visible. When the server boots, only 3 of the SAS card drives are visible. Boot down, swap the breakout cable to slot 2 on the SAS card, boot up, still only 3 of the SAS drives visible.

I will try a new breakout cable, failing that I will tryto update firmware of SAS card.

So odd it has happened after basically doing very little to the server.

[t2ffn]

This is my SAS card: supermicro AOC-SASLP-MV8

[t2ffn]

Ok, so tried all sorts of things now, different SAS cables, different power cables, all same result, only 3 of the 4 drives on the SAS card are visible, but all can be seen on the bios at boot.

I have checked, I have the newest driver. (There are some beta drivers about, but read one or two bad things so hmm)

I cannot get it to update the firmware from USB. Not 100% sure I'm doing it right either.

I will uninstall and reinstall, I've had the card out and back in but no joy...