zombie process

[Jolene Mellas]

Help!
I have a hung I/O process so kill -9 is futile on it, and the directory where my hung process is supposedly writing to is now locked and unaccessible. How do I unlock the directory and kill this process? Any help greatly appreciated.

[Pete Randall]

Jolene,

I wish I had better news, but the only way you're going to get out of this is to reboot. You can't signal the process to kill it because it's waiting on the I/O to complete and can't be interrupted in this state. There's no other magic way to unlock the directory.


Pete

[Jeff Schussele]

Hi Jolene,

Your only hope is if the parent PID for this process is anything but 1.
If so you can try to kill the parent & *hope* it's reaps it's child.
If the parent PID is 1, there's a small chance that it will reap the process eventually, but if it's hung on I/O that will never return then a reboot is probably your only way to get out of this state.

Rgds,
Jeff

[Sundar_7]

As noted above, I believe the only resort is to reboot the server.

If you execute shutdown -r -y 0 , I am skeptical if it is ever going to succeeed in rebooting the server.

I would rather suggest unmounting all the filesystems execute killall and then reboot -r command to reboot the server.

[Jolene Mellas]

the process is owned by root, so I'm not sure killall will work?

[Sundar_7]

why not ? - unmount all the filesystem and execute killall. this is not going to kill the hung daemon. But after umount and killall you can execute reboot command.

[Jolene Mellas]

it is not letting me umount the FS:
umount: cannot unmount /home : Device busy

[Patrick Wallek]

That is the catch here. The process is stuck waiting for I/O and you can't kill it, but you can't umount the filesystem because the process is still using it.

Not much to do except reboot. The machine *should* eventually shutdown. You will likely see a message like "Some user processes wouldn't die" or something similar.
The thing to do is figure out why the process is waiting on I/O. If there is any way to fix that problem, then you can continue normally.

[Sundar_7]

Yes I understand you cannot unmount the filesystem. I meant unmount REST of the filesystems.

I am not sure if shutdown will succeed it or not but you could give it a try.

[Muthukumar_5]

There is a chance that when the child process lost it's parent process ID to give their exit status and got the ppid of init (1) then it will be gone soon.

And more ( I did not try or not known), can we kill the zombie process's parent process to make it to 1 so that we can get the state of above?

As normal, only reboot / shutdown ( your choice ) to remove all zombie process

And discussion ( SEP, sundar)

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=641439

[Sยภเl Kย๓คг]

Give a reboo which is the better option at present
regards
SK