Umounting an NFS-mounted share after connection is lost?

[Thomas Mueller]

How do you umount a file system that has been mounted with mount_nfs when the connection is lost?

Server can crash, cable modem could quit and not hold power, or a change in cable modem or router could change 192.168.0.1 to 192.168.1.1 .

Running umount hangs the terminal session.  Is there a way out short of rebooting?

In the case of a server crash, I could reboot the server, mount the desired partition, run "/etc/rc.d/mountd restart", and be good again.

But last weekend, the cable modem-router lost power, could be restored by unplugging and replugging, but would only hold for maybe a half minute before going dark again.

Charter Spectrum support told me that I could get a free replacement, which I did, cable modem and router were two separate pieces this time.

I was able to install the equipment successfully but noticed that the router address was 192.168.1.1 rather than the old 192.168.0.1 .

I was left with /homeawayfromhome that I couldn't unmount except by rebooting.

Tom