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I'm running a Supermicro X7DCA board in a NAS server.

Whenever I plug in a sata disk the boot sequence goes out of order.

This is a problem, because it is running headless.

I've had this problem many times before with other consumer motherboards.

How to prevent this?

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Um, which operating system is in use? And what type of SATA disks are you adding? And why? – ewwhite Feb 20 '14 at 8:48
I'm running FreeBsd (freenas). But the error is at boot on the bios level. Sometimes I just need to plug and unplug things. – kareldc Feb 20 '14 at 9:27
I don't understand why you'd be adding arbitrary disks to a NAS or even rebooting often enough for this to be an issue. – ewwhite Feb 20 '14 at 12:55
Is that the X7DCA-3 or the X7DCA-L? Which BIOS revision? – Andrew Feb 20 '14 at 13:02
It is the X7DCA-3 I will check the bios revision. But there is a newer version available I think. Updating is a pain because I don't have access to dos to make a boot floppy... – kareldc Feb 20 '14 at 15:45

If you have physical access (to add disks) but it's headless, do one of two things (depending on physical constraints):

  1. Attach a KVM
  2. Use a crash cart

If you are only swapping disks the boot order should not change unless there is a BIOS bug; in which case, try updating or reflashing it.

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I see the same type of problem with my SuperMicro X7DCA-L with the latest BIOS (R1.2a), though I don't even have to change anything for it to happen. The machine just randomly decides to move things out of the excluded list and/or change the boot order. Sometimes I can reboot several times in a row before it happens, but it happens regularly.

I'm assuming that just like they can't be bothered to properly document their BIOS settings, keep their manuals up to date or package their BIOS updates packages with all of the parts needed to actually install it; they can't be bothered to write a properly working BIOS. This is especially sad given the premium they charge for their products and the market they're supplying.

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This is an excellent reason to use better hardware. This is what happens when people buy Supermicro versus something a bit more polished. Nagging little issues like clean BIOS upgrades can make a tremendous difference. – ewwhite Dec 6 '14 at 8:12

Attach a head, press DEL during POST, go into the BIOS Setup, and under the Boot tab modify the boot order to get (I imagine, since you said NAS) USB key to the top.

F10 to save and exit.

General procedure is same for all, specific keys and tabs differ.

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I need to avoid having to do this every time I attach a sata device (disk). – kareldc Feb 20 '14 at 9:28

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