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How do I get past single user mode in Mac OS X?

Please HELP !! My G4 PowerBook was in an auto accident. I'm running OS X Panther. It booted once just fine. NOW all I get is ":/ root#" One time a guy gave me a script that got me up and running, but I don't remember what it was.

Dave's Answer:

This sounds like a terrible situation and I'm certainly sorry to hear about your auto accident. While your computer doesn't heal in the same way that your body does, the situation you're in should be recoverable.

What's happening with your Mac OS X Panther PowerBook is that it's booting into single-user mode, rather than automatically moving through the different init states into multi-user, full GUI, network mode. You can force a Mac to do this by holding down the Command (cloverleaf) and S keys on boot up.

If nothing's significantly wrong, it might be acting weird so a first test would be to type reboot at the prompt and see what happens. One of three things can occur: it'll reboot and go into full GUI mode as if nothing was wrong (and perhaps nothing is wrong!), it'll reboot and go back to single-user mode, or it'll try to progress by scanning your hard disk for errors and fail with some horrible errors.

I'm only going to address that last scenario, as I bet that's what's wrong. To check your hard disk, you need to run a program on the command line (where you are when you stop the boot sequence in single user mode) called fsck (pronounced "eff-ess-check" by Unix cognoscenti).

The fsck program runs disk consistency checks similar to Disk Utility and other fancy applications, but at the command line. Every time you boot without shutting down properly, and once every 20 or so "clean" reboots, the fsck program analyzes the disk to ensure everything looks good.

Unfortunately, your disk probably doesn't look good. So you'll want to run the fsck program by hand and see what it finds. The easiest way to do that is to just type fsck -f and let it run. The program will probably find a pile of things wrong with your disk, just say "yes" to every "fix?" prompt and see how it goes. Once the fsck program is done, run it again. And again, until you can get through your disk without any errors reported.

If it reports errors each time and never cleans up, well, then you probably need to just reformat your hard disk and reinstall the operating system. Yech. It'd be worth taking your computer in to a repair center (or over to a Mac geek's house) and trying to remote mount the disk to salvage your personal data, but there are no guarantees at this point. Sorry.

If you do finally get through the fsck process, you should mount your root disk, which is to say, let the operating system hook it into the system now that you've run fsck to fix it. This is done with the command mount -uw /, which won't have any output if it works.

Finally, now you're ready to boot up properly. Type exit and keep your fingers crossed.

Good luck with this!

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Comments

Under OS 9.7 pre-OSx 10.3.9 firewire drive does not mount on a desktop any longer. Disk utility at some point reported "exit error." Now when I turn FW disk on, the message sugest to eject it or initialize it.

What does that mean to the prospect of repairing the disk or at least to recovering my data on it?

Posted by: bogdan at January 21, 2006 5:05 PM

Hmmm.... I would definitely stop trying to mount it and instead try to run a program like Apple's Disk First Aid or Norton Disk Utilities (I only barely remember Mac OS9 applications). Then with that running, plug in the drive, turn it on and hope that the utility can see it. If it does, great, run some of its disk management programs to try and fix the problem. If not, I don't know how you can proceed.

Posted by: Dave Taylor at January 22, 2006 10:53 AM

I have been searching the internet now for about 3 days but I can't find anything about my problem. But when I read the answer by Dave my hope came back.

My computer suddenly started up in single user mode a few days ago. I have done the reboot but I come back to the same place. I have done the fsck and the computer was ok.

I installed some extra ram about 6 month ago and someone said that I should try and remove the extra ram and try again since the problem could be with the ram. I have tried that but without any luck.

So what now? What can I do? What is wrong? Should I have it repaired?

Nothing special happened to the computer before this happened. I use the computer for graphical work, mainly website development. For this reason I have installed MySQL so I can use the computer as a local webhost for testing.

I hope you can give me an answer as I really don't know what to do.

Posted by: Jonas at January 29, 2006 3:48 PM

Hi Jonas. I really don't know what might be wrong with your Mac: you just cannot get beyond single user mode? What happens when you boot into single user mode and type "exit" on the command line?

That should let the computer continue its bootup and go into multiuser mode (regular run mode)

Posted by: Dave Taylor at January 30, 2006 9:44 AM

When it boots into single-user mode, did you try typing mac-boot?

Posted by: Adam Kerney at May 8, 2006 10:38 PM

Help! I launched into single user mode, and got a command line. I started to type fsck when suddenly, a process started running. The process started with USBF: and then a bunch of other stuff, and it keeps going. I can never get another command line. Any help is greatly appreciated!

Posted by: Jeremy Sykes at July 20, 2006 6:14 PM

Jeremy: Keep typing the whole command (fsck -fy) and press enter, even if the command line is interrupted. The USBF messages are likely just the system notifying you that something is going on with USB, the messages are harmless, and the fact they are overlayed on your command line does not mean they are interrupting what your typing, just making _seeing_ what your typing more difficult :)

Good luck!

Posted by: Superman at August 3, 2006 1:31 PM

I am having a similar problem. My Mac running OS 10.4 was hung and a forced power down and reboot landed it at # prompt with an error on /etc/master.passwd. I noticed that while my user data is intact and /etc, /var and /tmp are now link pointing to some garbled name with ??? signs in them. Please help. My biggest concern is backing up my data that accessible and intact now. I have an external firewire drive but it does not appear to be mounted now. mount only show /, /dev and another paritions. When I go /Volumes I see the mount point for external disk but it is not mounted. Can I get back my /etc and /var and /tmp directoties ?

Posted by: Sandeep at March 1, 2007 6:44 AM

Hey man I am having no luck getting out of single user mode and into my Mac OSX. None of the commands you provided get any repsonse. First, I login and provide my admin PW, and I get a command line with "[my computer name]$"...

If I enter "Rebooot" I am told "operation not permitted"

If I enter "exit" I logout and am returned to the Login/PW command lines in darwin.

...the "fsck -f" command gets no response.

Is there a way I could hook up a fire-wire HD and get my info out of there...then reinstall the OS? The computer is a 6 month old intel MacBook Pro, with a windows partition.

I am able to start up in selective mode, and if I choose the windows OS it starts up fine. IF I select the MAC it does not (it goes to the Darwin/BSD console window with login/pw prompts). I don't know if it is relevant, but I changed the name of the HD yesterday from "Macintosh HD" to "MAC"...I certainly did not think this would result from such a little thing.

Posted by: Brian at March 1, 2007 9:59 AM

I'm having the same problem. Somehow I'm booting into single user mode. (I never even knew there was such a thing.) I've tried various reboots, including X and mac-boot. I've tried exit. I've tried logout. Nothing gets me out of single user. If I reinstall the operating system, will I lose everything I haven't backed up? If I reinstall, will it bring back the multiple user mode? I'm desperate at this point.

Posted by: Cher at May 20, 2007 10:07 AM

fsck isn't pronounced "f-s-check" by sysadmins... "fsuck" is most common, but usually the s is silent.

http://en.wikipedia.org/wiki/Fsck#Use_as_profanity

Dennis Ritchie: "So fsck was originally called something else"
Question: "what was it called?"
DMR: Well, the second letter was different.

Posted by: Mark Hughes at August 16, 2007 12:19 PM

I'd like to say thank you for all. I'm experiencing this problem. I hope that I can fix it.

Posted by: Lai Duc Tien at January 20, 2008 7:30 AM

If none of that works you can remake your own admin account without messing with any other accounts and boot like the computer was brand new... first when you log in go to single-user-mode and type in "/sbin/mount -uw /" and it should say something about unlinked files or something.. if not.. it's okay.. then just type "rm /var/db/.applesetupdone" this basically removes the apples done set up without messing with any accounts or memory or saved things and there are no risks what so ever... then type "reboot" to reboot and let it go through to the start-up an fill in the info from your new admin account and once you make it log in as it and you can fix, change anything, access any accounts, and delete any accounts.. Note: this could be used for hacking anyones mac and works on ANY version on mac.

Posted by: Jon W at March 22, 2008 1:17 AM

ok, so i went to use my daughter's computer today and it got stuck on the grey apple start up screen with the gear spinning endlessly.

I attempted to hard boot in single user mode so that I could use the fsck command to repair any potential issues but the script never takes me that far...meaning I never get to a prompt to enter any script.

any suggestions....

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I do have a comment, now that you mention it!