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I have Ubuntu 10.04.1 (Lucid) running on a 2010 Mac Mini (4,1). It's a server, so I want it to be able to restart after a power failure ("server mode").

In Mac OS X, you can check "Start up automatically after a power failure" in the "Energy Saver" System Preferences. However, having this value checked doesn't seem to effect "server mode" behavior in Ubuntu (that is, it won't restart after a power failure).

This seems to be because the "server mode" value isn't persisted in pram/efi, but gets set by Mac OS X on every boot.

I found this tutorial on how to turn on "server mode" for a Mac Mini, but it doesn't work:

$ setpci -s 0:1f.0 0xa4.b=0
setpci: Warning: No devices selected for `0xa4.b=

A lot has changed with the new 4,1 Mac Minis-- just getting Ubuntu installed on it was quite a feat. Perhaps the "server mode" incantation has changed also?

My question is: how do I enable "server mode" on the new 4,1 Mac Minis?

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migrated from serverfault.com Nov 18 '10 at 19:19

This question came from our site for professional system and network administrators.

In my experience, this is something typically handled by the bios. Since I know nothing about the lower workings of a Mac (other than that they use mostly standard Intel processors), I wouldn't be able to tell you how set the necessary values in the bios, let alone how to get into it in the first place. –  MBraedley Nov 18 '10 at 22:35
You mean EFI, not BIOS. Anyway there's no EFI setting for this. It's a chipset register that has to be poked on every bootup. I wish it were in the EFI, or in the pram at least, then we'd only have to set it one time! –  paleozogt Nov 18 '10 at 23:42
My point exactly. –  MBraedley Nov 19 '10 at 2:59
The current solution does not work for Mac Pro, but you can check this bug at Ubuntu bugs.launchpad.net/ubuntu/+source/linux/+bug/784571 –  sorin May 18 '11 at 13:00
@Sorin Sbarnea: well, the question is for a mac mini –  paleozogt May 18 '11 at 14:54

1 Answer 1

up vote 5 down vote accepted

I found the answered buried in this post. The new setpci command is

sudo setpci -s 00:03.0 0x7b.b=19

btw, this setting isn't "sticky" and won't persist across reboots-- it has to be set upon each boot.

You can put this command in a bash script and run it on startup. See here for details on start-up scripts.

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Can you run that command in a start-up script, or will it still ask you for the su password? –  MBraedley Nov 19 '10 at 3:01
Yes you can run it in a start-up script. I've edited the answer to link to a start-up script how-to. –  paleozogt Nov 19 '10 at 16:03
Could you be so nice to add information regarding where to add this line in order to assure that it will be executed when the system boots, preferably as soon as possible? - Ubuntu –  sorin May 18 '11 at 11:32
@Sorin Sbarnea: in the answer is a link to info on start-up scripts in ubuntu –  paleozogt May 18 '11 at 15:00

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