We have 2 Amazon ec2 AMI linux instances (2017.03) that have mounts pointing back to different windows servers in our office and other locations using cifs. These mounts have been up for about 2 months with no issues until about 2 or 3 days ago. Now we are getting intermittent connectivity issues.
For example, sometimes when I do:
ls /mnt/qdrive
it works, but sometimes I get:
ls: cannot access /mnt/qdrive: Host is down
If I wait a few seconds and try again, it works. I have tried having 1 putty window open that is pinging the server and in another running the ls command and the ping comes back with data every time, but I get the Host is down error.
I also tried restarting the smb service, but it didn't seem to matter.
What would cause this type of intermittent connectivity? Is there anything I can do to fix it?
/var/log/messages
that might indicate an issue with CIFS? When it is mounted whats in/proc/fs/cifs/DebugData
?