mount error(112): Host is down

I’ve encountered this error a few times lately when trying to mount a CIFS share from Linux, and didn’t get much help from Google.  Obviously, I knew the host wasn’t down.  I tried several things, to no avail, so I busted out my trusty wireshark.  Lo and behold, there was a TON of traffic going back and forth between my Linux server and my CIFS server even though nothing was mounted.

It turns out that earlier, a previous mount attempt (maybe the automount on boot?) had gotten stuck and was spewing traffic.  I killed that stuck process, and everything was happy again.

Weird.  I hope that helps somebody else.