Ubuntu won't boot: run-init: /sbin/init: Permission denied and /bin/sh: 0: Can't open splash

Question

Last night everything was fine with my Ubuntu 16.04. Today I tried to turn it on and it simply won't boot, throwing these errors:

run-init: /sbin/init: Permission denied
Target filesystem doesn't have requested /sbin/init.
run-init: /sbin/init: Permission denied
run-init: /etc/init: Permission denied
run-init: /bin/init: No such file or directory
/bin/sh: 0: Can't open splash

• It does not give me any kind of shell
• I tried the recovery item in the GRUB menu, but the same error appears
• I also tried adding systemd.unit=rescue.target as a kernel parameter; it didn't work either.

How can I solve this problem?

Solution

As we can see in the messages you get, the most possible cause is a permission issue. Also it seems that /sbin/init and /etc/init exist but /bin/init does not.

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Get rid of /bin/sh: 0: Can't open splash

First we should get a shell to fix the problem. To get rid of /bin/sh: 0: Can't open splash and get a shell: If you only have an Ubuntu installed (GRUB will not appear by default), while the system is booting hold the shift key to make GRUB appear. Then on the default menu press E.

You will find a line starting with Linux. At that line remove the splash parameter and then press Ctrl+x, now you will be dropped into a sh shell. Run /bin/bash to get a bash shell if you want to. I prefer bash over sh because it has auto-complete functionality.

Alternatively instead of removing splash parameter, you can add init=/bin/bash at the end of that line and then press Ctrl+x; this time we'll be dropped into bash instead of sh.

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Fix the run-init: /sbin/init: Permission denied

Run:

ls -lH /sbin/init

It should produce something like:

-rw-r--r-- 1 root root 1577000 Feb 15 12:20 /sbin/init

As we can see permissions are messed up. in almost all systems these days /sbin/init is a link to systemd, just to make sure:

# ls -l /sbin/init
-rw-r--r-- 1 root root 1577000 Feb 15 12:20 /sbin/init -> /lib/systemd/systemd

Sure it is, your / (root) file system is mounted in ro state (Read only), lets change it to rw (Read and write):

# mount -o remount,rw /

Then fix the permissions:

# chmod u=rwx,g=rx,o=rx /lib/systemd/systemd

Reboot the system.