Linux: mount.cifs failed with host is down
due to some security issues (Wannacry) Windows administrators are going to disable the unsecure smb1 protocol.
mount.cifs is using smb1 by default. So when you tried to connect to a Windows machine where smb1 is disabled you get an error: mount error(112): Host is down.
root@devdeb ~ # mount -t cifs -o user=yourWindowsUser,workgroup=yourDomain //yourWindowsMachine/share\$ /mnt/yourWindowsMachine mount error(112): Host is down
To establish a connection nevertheless you have to force the use of smb2
root@devdeb ~ # mount -t cifs -o user=yourWindowsUser,workgroup=yourDomain,vers=2.0 //yourWindowsMachine/share\$ /mnt/yourWindowsMachine