SystemRescueCD has the option to locate existing operating systems on a system and give you the option to boot one of your choice. It lists them in the boot options as findroot. Is there a command to do the same after it boots to the command line? The system I used takes too long time to boot SystemRescueCD choice menu and by the time I get to the screen the regular prompt is showing. Can the command which locates the existing OS and presents the menu on which one to boot be run from the command line?

This is my first post so if I do something wrong I would appreciate it if you correct me so I am able to resolve the issues for future posts. I was in the middle of an upgrade when I accidentally logged out. Now when I try to log back in it gives me the **"Oh no! Something has gone wrong."** message telling me **"...the system can't recover."** I tried logging into the console via recovery mode but it tels me **"Cannot open access to console, the root account is locked."** I am unable to type any commands, all I am able to do is press enter. When I do that I notice some messages stating system files are messed up and it is placing new files in for compatibility purposes. It goes by pretty quickly so I am unable to get a picture or even read exactly what it says. I also tried the trick where you edit the recovery mode option within the Grub menu to allow you to gain access by giving you root access without the need of a password but that didn't do anything. Thanks in advance for any help, it will be very much appreciated! ***Edit: First of all, thank you all for answering my post and trying to give some guidance! The thing is that I used to use Kali as my daily driver so I had built up pictures and other person items that I've comed to treasure, however, it was only after seeing the post by @Marcus-Müller that it dawned on me! You see I tripple boot Windows 11, Ubuntu 24.04, and Kali Linux so I was able to get into my Kali partition and copy everything from my home folder. I'm doing this now and will create a live usb and reinstall my Kali OS. Once again I'd really like to thank everyone of you for not chastising me and giving me real-world solutions! ~Ryan

After edited the /etc/security/limits.conf file to set the nofile parameter to unlimited, server got hanged . Can't login in via ssh. Tried to take console, issue with console. Will reboot of the VM will solve the login issue ?

Looking for **WRITTABLE** resque/recovery type LINUX distro for USB flash drive under 8GB installed. Current primary usage scenario: write and troubleshoot initramfs script for non-standard boot process (details doesn't really matter here). By "resque type" I mean without heavy stuff like office/video/multimedia, not necessary loaded with all kinds of recovery tools. Should support/have: - minor **soft installation** and fstab, other /etc files modification (i.e. ROOTFS need to be WRITTABLE, or /etc at least) - mount of LUKS + BTRFS partitions & subvolumes - able to run Bash scripts - have (or be able to install) plain text editor (will be used for shell scripts editing) - Terminal - Chroot (or be able to install) I tried Systemresque 10.02, which has touchpad DISABLED (there's a ticket on gitlab for 3 years about this). One cannot even install any of recent versions 11.x with their own USBWriter, and has other issues noticable almost immediately. Otherwise Systemresque would fit the target. Haven't given up on Systemresque completely yet though. Most of the time I spend in dual panel file manager or in terminal, therefore GUI isn't important. Interface similar to Cinnamon or Windows 7 would be best if there's a choice, but again not important. This is a laptop with 1 disk, therefore installing full size distro to another disk is not an option. Thank you.

A couple of days ago, I tried getting an old server of mine up and running.  It was working initially, but after updating and rebooting the system a few times the system refused to boot, dying at GRUB Rescue. I put the hard drive in another Linux machine to see what was going on, and the system partition was displaying as unknown.  I ran "fsck" on the partition, which got it working again; however, now the "var" and "usr" folders are missing! I've tried various things to try and recover the data, including running "Check" and "Attempt Data Rescue" (which crashes) on GParted, fsck, testdisk, changing the superblock, creating and mounting an image using DD, and nothing seems to work.  Even worse is, the files I want to recover are not in the "lost+found". The partition type is ext3. The partition reports "5 GB" of data is in use; however, only around "2.8 GB" can be accessed. I've tried doing a PhotoRec on the hard drive, but it seems completely pointless, as any recovered files are unnamed, so it'd be impossible for me to recover anything in a sensible manner.

I was originally using windows 10 when I had formatted my system twice to use ubuntu and now i have installed linux mint. Is there any chance I will be able to recover those old files? I am currently trying my luck with testdisk and then I'll try photorec. Any suggestion is appreciated.

After a power outage, my ubuntu 20.04 boots from the normal option in grub to a black screen and hangs there. However, if I go to Advanced Options and select recovery mode and then "resume", it is able to boot up. What went wrong? how can I fix it? Note: I found many solutions to this problem, not all worked for me so I figure that there are many things that could go wrong. It might be nice to have many optional solutions listed in the answers for this problem :)

I have an encrypted hard drive. The hard drive, root user, and primary user all share the same password. I have successfully logged in but seem to have forgotten the password. I'm looking to limit the damage of this forgotten password and attempt to recover it. The steps I am taking so far are the following: * Write down the password as best I can remember it. * Email a copy of /etc/passwd to myself so I can attempt to run a brute force attack on it with the characters from the prior step. * Backup unsaved data and files as best I can. Does anyone have any suggestions on a tool to use to brute force /etc/passwd? Update: It looks like the hashed passwords are now in /etc/shadow so if I want to run this brute force I need to do it now while I have a login prompt... I have no root shell and cannot sudo since it's the same password.

I strongly despise any kinds of automatic OOM killers, and would like to resolve such situations manually. So for a long time I have

vm.overcommit_memory=1
vm.overcommit_ratio=200

But this way, when the memory is overflowed, the system becomes unresponsive. On my old laptop with HDD and 6 GB of RAM, I sometimes had to wait many minutes to switch to a text VT, issue some commands and wait for them to be executed. That's why I have numerous performance indicators to notice such situations beforehand, and often receive questions why would I need them at all. And they don't always help too, because if a memory overflow happened when I wasn't at the laptop, it's too late already. I suspected the situation would be better on a newer laptop with SSD and 12 GB of RAM, but in fact it's even worse. I have zRam with vm.swappiness=200, which allows up to 16.4 GB of compressed swap, and when it's nearly extinguished, the system becomes even more unresponsive than on the old laptop, to the point even VT switch barely works, as well as I cannot SSH into the system from the local network, so my only resort is blindly invoking the kernel's manual OOM with Alt+SysRq+RF, which sometimes chooses to kill important process like dbus-daemon. I might make a daemon with a sound alert when the swap is almost full, but that's a partial stopgap again, as I may not come in time anyway. In the past, I tried to mitigate such situations with thrash-protect. It sends SIGSTOP to greedy processes and then automatically SIGCONT-s them, which helped a lot to postpone the total lockup and resolve the situation manually, but in strong overload conditions, it starts freezing virtually everything (which can be explicitly allowlisted though). And it has a lot of irritating side effects. For example, if a shell is frozen, its child processes may remain frozen after thawing the shell. If two processes share a message bus and one of them is frozen, the messages are rapidly accumulated in the bus, which leads to rapidly growing RAM usage again, or lockups (graphical servers and multi-process browsers are especially prone to this). I tried to run sshd with a -20 priority, like suggested in the [similar question](https://unix.stackexchange.com/questions/45451/reserve-resources-for-admin-console) , but that doesn't really help: it's as unresponsive as with the default priority. I would like to have some emergency console which is always locked in RAM and is usable regardless of how overloaded the rest of the system is. Something akin to Ctrl+Alt+Del screen in Windows NT≥6, or even better. Given that it's possible to reserve some RAM with the crashkernel parameter, which I use for kdump, I suspect it's possible to exploit this or some other kernel mechanism for the task too?

And now I am unable to chmod it back.. or use any of my other system programs. Luckily this is on a VM I've been toying with, but is there any way to resolve this? The system is Ubuntu Server 12.10. I have attempted to restart into recovery mode, unfortunately now I am unable to boot into the system at all due to permissions not granting some programs after init-bottom availability to run- the system just hangs. This is what I see: Begin: Running /scripts/init-bottom ... done [ 37.062059] init: Failed to spawn friendly-recovery pre-start process: unable to execute: Permission denied [ 37.084744] init: Failed to spawn friendly-recovery post-stop process: unable to execute: Permission denied [ 37.101333] init: plymouth main process (220) killed by ABRT signal After this the computer hangs.

I'm on Arch Linux, and I intended to run "sudo rm ./\*" to clear out one of old dirs, and I accidentally omitted the dot and ran "sudo rm /\*". How could I recover at least some of my old files?

I had to perform a hard reset after my machine became unresponsive. Now when I try to boot, it hangs as shown in this image:  . I am able to boot into recovery mode, so have access to a terminal I can use to fix the problem, but I'm just not sure what that fix is. $ uname -a Linux Kali 4.8.0-kali1-amd64 #1 SMP Debian 4.8.5-1kali1 (2016-11-04) x86_64 GNU/Linux Here is some info on graphics drivers: 

I have a head node and 4 worker nodes for high-performance computing (HPC). Recently, I had to turn it off for maintenance at our data center. I tried to turn the system back on, but I encountered an error message stating

[ 5.215623][ C14] nvme0: Identify(0x6), Invalid Field in Command (sct 0x0 / sc 0x2)
You are in emergency mode. After logging in, type "journalctl -xb" to view system logs, "systemctl reboot" to reboot, "systemctl default" or "exit" to boot into default mode.
Give root password for maintenance (or press Control-D to continue):

and it seems to be stuck in a loop. Initially, I selected Ctrl+d as suggested to boot into the default mode, but unfortunately, it just recycles back to the same emergency mode error every time. A couple of things that might be relevant: * I wasn't aware, but it seems an external USB was left plugged into the system's back when I turned it on after maintenance. I'm not entirely sure if this could be causing the issue, but it's worth mentioning. * Each node requires two power cables plugged into the power adapter. During the reconnection, I realized that one of the power cables for a node was not initially connected to a power source. However, I have fixed this issue, and now all nodes are receiving power as required. I'm not a Linux expert, so I'm a bit lost as to what could be causing this problem. I've tried searching for solutions online, but nothing seems to be working for me. If any of you have encountered a similar issue or have expertise with SUSE Linux and HPC systems, I would greatly appreciate any advice or guidance on how to troubleshoot and resolve this "emergency mode" problem.

Unfortunatelly I made mistake somewhere but can't get where. I had issues with ssh and github, tried different things and they didn't work. Later I decided .. i think.. moved file i balieve it was home/username/known.hosts or smth like that. Additonally I deleted everything from folder, where id_25519 and id_25519.pub files (maybe they are related to github, i don't know). And somewhere in between or afteer all. I could not provide my password in terminal. I 200% sure it's correct, no caps/num/ other things used. and now i can't log in to my linux mint cinamon 20. I will really appreciate any help how can I recover my laptop. It starts, but requires pass. And I can't understad how coudl it change ......

I'm currently testing a backup/restore of RHEL 6.4 OS via the "dump" and "restore" on testing environment, and I do know that RHEL 6.4 seemed too outdated in nowadays. Butsome enterprises are still using such version of RHEL to load their services. **Here's the scenario**: to backup the system and critical programs in case of host crash/failure event. * The test RHEL 6.4 host for backup utilizes windows Hyper-V VM as infrastrucure and the OS root is installed on LVM logical volume. * In order to backup the system, I placed system into single user mode and used command to backup the root filesystem

-shell
    dump -0uf //mybackup.dump /

* The dump showed "DUMP IS DONE" on screen and the dump file was created with size about 2.2GB therefore I believed that the backup was successful. In order to simulate host crash event, I reinstalled the RHEL 6.4 system utilizing LVM logical volume and boot the system into single user mode before restoration. However, after restoring root filesystem using

-shell
restore -rf //mybackup.dump

The screen showed kernel panic and some other errors, and hung eventually. I retried several times but always failed. Can anyone give me some hints why the restoration can't be completed?

I upgraded Debian stable from 11 to 12 today by

apt-get upgrade

. Thousands of packages were downloaded. However while packages were being upgraded the system froze. I manually shutdown by pressing the power button for 10 seconds. Next boot I was stuck in a hardware error message loop so I had to reboot again. This time it booted successfully. Some notable changes include the Debian 12 logo on the boot screen as well as a missing background because the stock backgrounds were replaced. I tried

apt-get upgrade

but got an error saying

was interrupted

. I ran

dpkg --configure -a

and got the following response:

dpkg: warning: 'ldconfig' not found in PATH or not executable
dpkg: warning: 'start-stop-daemon' not found in PATH or not executable
dpkg: error: 2 expected programs not found in PATH or not executable
Note: root's PATH should usually contain /usr/local/bin, /user/sbin and /sbin

Then I attempted

apt-get upgrade

again. This time it did let me upgrade while letting me know that hundreds of packages were not fully installed. But it froze again. What is worse, after a reboot I was greeted by the GRUB shell. I had to use the following commands to escape to the GRUB GUI.

set prefix=(hd0,2)/grub
set root=(hd0,2)
insmod linux
insmod normal
normal

Fortunately I was back in Debian. However a third attempt at finishing the upgrade failed when

-reconfigure libdvd-pkg

froze the system. I was back at the GRUB shell. This time it returned errors while hanging for an extended period of time in

, saying it was unable to read a certain sector. After yet another reboot, I was able to use the same set of commands to get back into the system. Having gone through a roller coaster of emotions, I am scared to upgrade packages now. While

apt-get upgrade

shows that no more packages are hanging in an intermediary state, thousands of packages were held back. I went to GNOME Software app which displayed the same list of updates available. It displayed the option to begin the upgrade. My questions: 1.

dpkg --configure -a

still gives me the same warnings and errors. Do I need to manually insert the missing executables? 2. Why are so many apps blocked from upgrading in CLI but not so in GUI? Is it safe to upgrade, given that my computer already failed to do so multiple times? 3. I do not want to transit the GRUB shell every time I boot. How do I repair it? 4. After resolving 1-3, is it safe to assume that everything else is fine, brush it off and move on? Are there tools that resemble

and

of Windows that automatically scan the system for damages? 5. How do I backup the entire system so that GRUB can fall back to it in case of a unrecoverable accident? I do backup personal files manually on a thumb drive that has no where near the capacity to store the system. However my SSD's total space is more than double the size of all partitions combined and could thus store a copy of all of them.

I am using btrfs (which seems integral to the question). Upon recovering with timeshift and rebooting, I am encountering the following error [Failed] Failed to mount /home. [Depend] Dependancy failed for Local File Systems You are in emergency mode. After logging in, type "journalctl -xb" to view system logs, "systemctl reboot" to reboot, "systemctl default" or "exit" to default mode. Obviously, Control-D, rebooting and default mode etc. do not work. I tried timeshift --restore and I get the following error. It says "Found stale mount for device /dev/nvme0n1p2 at path /run/timeshfit/837/backup. \n Unmounted successfully. \n E: Failed to remove directory. \n Ret=256". I think the problem is, that it can not mount /dev/nvme0n1p2 to /home. But I am not sure how to fix it. Would really appreciate some help sad Cheers. P.S. here is my /etc/fstab output, when I log in as root (after emergency boot) I have a feeling, that typing mount /dev/nvme0n1p2 /home might fix it, but I am afraid it might just wipe the drive or something...

My root partition had no space to the point that couldn't login. So invoked Ctrl+Alt+F2 and ran to free disk space:

find / -xdev -name core -ls -o  -path "/lib*" -delete

Now can't even initialize OS after GRUB, it days:

run-init: can't execute '/sbin/init' No such file or directory
run-init: can't execute '/etc/init' No such file or directory
run-init: can't execute '/bin/init' No such file or directory

How can solve that?

I cannot boot into my installed Fedora 37 after moving around partitions. I have spent a week trying to fix the issue so have decided to cut my losses and assume I'll never get back into it. I have been booting Fedora 37 from a live USB since the issue occurred and I can see my old OS's partition on Disks/Gparted so I know the data is still there. What is a way to extract the files from within the partition using a live boot?

A newcomer to linux here, I was trying to set a custom display resolution and make the changes permanent but looks like I've forgotten something and the login screen won't come up (the only thing I'm seeing is the black login screen that asks for username and password.) I was trying to create a new file with two commands for xrandr so I could have a custom resolution, but after the recent reboot, I'm stuck on the black screen (tty1 thing) Anyway, I tried to reverse the process and find the file I created somewhere which I can't remember the exact location. The only way to undo this, is to use the command line as normal user (and not the root), so that I can figure out which file and where I've created. So far I've tried using command line in the recovery menu but since it's root, I won't be able to view the history of the previously used commands and using the "exit" command will bring back the menu. How can I achieve that? Unfortunately I cannot use live flash / cd to fix this because there's something wrong with my pc bios. Any help and suggestion is highly appreciated. P.S: I used google's web history to find out which websites I've visited so I could find what command I used, but failed; I couldn't find it.