When running umount /path I get:

umount: /path: device is busy. 

The filesystem is huge, so lsof +D /path is not a realistic option.

lsof /path, lsof +f -- /path, and fuser /path all return nothing. fuser -v /path gives:

 USER PID ACCESS COMMAND /path: root kernel mount /path 

which is normal for all unused mounted file systems.

umount -l and umount -f is not good enough for my situation.

How do I figure out why the kernel thinks this filesystem is busy?

Edit:

I have made a page with examples of all solutions so far here: http://oletange.blogspot.com/2012/04/umount-device-is-busy-why.html

When running umount /path I get:

umount: /path: device is busy. 

The filesystem is huge, so lsof +D /path is not a realistic option.

lsof /path, lsof +f -- /path, and fuser /path all return nothing. fuser -v /path gives:

 USER PID ACCESS COMMAND /path: root kernel mount /path 

which is normal for all unused mounted file systems.

umount -l and umount -f is not good enough for my situation.

How do I figure out why the kernel thinks this filesystem is busy?

When running umount /path I get:

umount: /path: device is busy. 

The filesystem is huge, so lsof +D /path is not a realistic option.

lsof /path, lsof +f -- /path, and fuser /path all return nothing. fuser -v /path gives:

 USER PID ACCESS COMMAND /path: root kernel mount /path 

which is normal for all unused mounted file systems.

umount -l and umount -f is not good enough for my situation.

How do I figure out why the kernel thinks this filesystem is busy?

I have made a page with examples of all solutions so far here: http://oletange.blogspot.com/2012/04/umount-device-is-busy-why.html

When running umount /path I get:

umount: /path: device is busy. 

The filesystem is huge, so lsof +D /path is not a realistic option.

lsof /path, lsof +f -- /path, and fuser /path all return nothing. fuser -v /path gives:

 USER PID ACCESS COMMAND /path: root kernel mount /path 

which is normal for all unused mounted file systems.

umount -l and umount -f is not good enough for my situation.

How do I figure out why the kernel thinks this filesystem is busy?

Edit:

I have made a page with examples of all solutions so far here: http://oletange.blogspot.com/2012/04/umount-device-is-busy-why.html

When running umount /path I get:

umount: /path: device is busy. 

The filesystem is huge, so lsof +D /path is not a realistic option.

lsof /path, lsof +f -- /path, and fuser /path all return nothing. fuser -v /path gives:

 USER PID ACCESS COMMAND /path: root kernel mount /path 

which is normal for all unused mounted file systems.

umount -l and umount -f is not good enough for my situation.

How do I figure out why the kernel thinks this filesystem is busy?

Edit:

I have made a page with examples of all solutions so far here: http://oletange.blogspot.com/2012/04/umount-device-is-busy-why.html

When running umount /path I get:

umount: /path: device is busy. 

The filesystem is huge, so lsof +D /path is not a realistic option.

lsof /path, lsof +f -- /path, and fuser /path all return nothing. fuser -v /path gives:

 USER PID ACCESS COMMAND /path: root kernel mount /path 

which is normal for all unused mounted file systems.

umount -l and umount -f is not good enough for my situation.

How do I figure out why the kernel thinks this filesystem is busy?

I have made a page with examples of all solutions so far here: http://oletange.blogspot.com/2012/04/umount-device-is-busy-why.html