"bus error" when trying to reboot Linux

When trying to reboot a Linux server I got the typical 'System going down for reboot now', but the server has not rebooted. I have tried:

reboot
shutdown -r now

The runlevel command returns 5. Any other options for getting this server to reboot? This is a remote machine, so I don't want to just shut it down if I can avoid that.

I am trying to reboot because of a journal abort on /, so / is read-only. Most commands now return 'bus error'

Solution 1:

Kyle, I'm not quite sure if this is what you're looking for (since it's like pressing the reset button), but this has helped me in situations where a server refused to reboot:

echo 1 > /proc/sys/kernel/sysrq  
echo b > /proc/sysrq-trigger

The first line is for enabling SysRq, and the second one is for rebooting.

See emergency reboot or shutdown with magic commands for more details.

Solution 2:

What does the end of dmesg output?

From the description is sounds like you may have a serious hardware issue that will prevent you from being able to reboot, as the commends you've given should have done the job for you already.

Otherwise the only think I know of is issuing commands directly to init using telinit, but I thought that that was what shutdown and reboot both basically did anyway.

Solution 3:

This kind of problem can occur if the disk subsystem is not available due to a RAID controller failure or hard disk failure. Binaries and libraries which are still in memory/disk cache can still be run but any other binary fails with IO errors or other fatal errors. If the reboot binary is still runnable then reboot -fn will force an immediate warm boot of the system. If the hardware is still functional you should be back in about 5-10 minutes, otherwise the system will be offline until someone can physically get to it to repair/replace it.