Recovering from Linux boot failure with fsck

A virtual Linux machine used for development was behaving unreliably.

Programs would fail to start and running program would freeze.

I decided to restart the system, however it failed to start up again.

 

It simply displayed this message:

BusyBox v1.22.1 (Ubuntu 1:1.22.0-15ubuntu1) built-in shell (ash)
Enter 'help' for a list of built-in commands.

(initramfs)

 

I tried to exit the shell, which lead to this message:

/dev/sda1 contains a file system with errors, check forced.
/dev/sda1:
Inodes that were part of a corrupted orphan linked list found.

/dev/sda1: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
        (i.e., without -a or -p options)
fsck exited with status code 4
The root filesystem on /dev/sda1 requires a manual fsck

 

File system corruption seemed to explain the reliability problems and the subsequent boot failure.

Followed the suggestion of running fsck with:

fsck /dev/sda1

 

Accepted all file system repairs suggested by fsck.

(Should have used the -y parameter)

 

Then rebooted the system with:

reboot

 

After the file system repairs the system booted and seemed fully functional.

Conclusion

If a Linux system fails to boot and only displays a BusyBox / initramfs prompt, try exiting the shell.

This may provide information about the actual problem.