0

I know that a lot of questions have already been asked about emergency mode when booting a Linux distro. (Seemingly Mint, Ubuntu, Redhat all have it.) Does it have documentation? What entity does it belong to (i.e. the Linux kernel, the distribution, the library)? I am just trying to orient myself, and all the information I have been able to find is of the form "do this and it will go away."

Thanks in advance.


It looks like there is possibly more than one emergency mode that can be entered during boot. I am also interested in knowing how to tell which one is which and where to get documentation for it. In my particular case, the Linux Mint symbol appears for a while and then the message "Welcome to emergency mode! After logging in, type "journlctl -xb" to view system logs...Give root password for maintenance."

1
  • The best way to show us what's happening is to let your computer turn off for let's say 5 min and booting it ; afterwards, type the following command: journalctl --since "5 minutes ago > boot.log" . If you cannot open a terminal in your desktop environment, use CTRL+ALT+F2 to be prompted with a "raw" shell. Finally, find a way to copy/paste the contents of the file boot.log you created in your question. – Paradox Aug 8 '19 at 19:57
1

The most common "Emergency mode" is the one entered by your boot system (e.g. GRUB or the next stage, systemd) when the system cannot set up all the hardware it is supposed to set up (e.g. no matching graphics driver for the hardware, partition missing / cannot mount everything in /etc/fstab) etc.

The way to deal with the emergency mode is dependent on the stage the system is in, and the specific errors that caused it (it is very important to read all error messages here).

The prompt might tell you which system you are in ("open" prompt: likely GRUB, asking for root password: systemd or some other init variant).

EDIT: Your emergency message prompts you for your root password. This is systemd or a similar init process talking. Please carefully examine the messages that come before this prompt to find out what the problem is.

6
  • Thanks for answering. So it sounds like there are two common emergency modes when booting, one by GRUB and the other by systemd. In my particular case, I see the Linux Mint logo before any emergency mode appears. Presumably this means that systemd emergency mode is the one I am facing? I was just digging into the GRUB documentation to see if it has anything. – Zach Boyd Aug 8 '19 at 19:34
  • @ZachBoyd Please detail the error messages, otherwise it is still unclear. Sometimes it helps to record a video of the booting process to watch it in steps, and see what the error message is. You are looking for something like "cannot mount ..." or "... fails/failing" close to the end, and perhaps right before the message that emergency mode will (therefore) now be entered. The prompt inside the emergency mode might also tell you which system you are in (type "help" if nothing appears). Are you asked for the root password, or is there an "open" prompt? – Ned64 Aug 8 '19 at 19:41
  • Thanks. I added the message at the beginning of the prompt. There is no other error message besides the system logs. Based on what you are saying, this might be owned by systemd rather than grub? The Mint documentation did not have reference to emergency mode, although I have not found detailed systemd documentation specifically yet... – Zach Boyd Aug 8 '19 at 19:50
  • @ZachBoyd OK, I edited your Question title, hopefully making it more clear. Feel free to edit some more. – Ned64 Aug 8 '19 at 19:57
  • Thanks @Ned64. Looking through man pages, it looks like I am dealing with systemd's emergency.target. I am still struggling to find anything that says what emergency mode is or what I am allowed to do in it, but I am not a pro at systemd stuff. Any ideas on where to find an actual description by the systemd people on what emergency mode is supposed to be? I feel like there should be a man page or readme somewhere. – Zach Boyd Aug 8 '19 at 20:16

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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