You want to access one shared directory from a linux machine to another linux machine.
That requires for the machine that has the shared dir to run the NFS server and client softare. Check through YaST2 to install the NFS packages for the server
Then follow
this simple quide on how to setup an NFS server, export the directories and mount them from the network.
Check back if you have any problems
Cheers,
Vangelis
EDIT: I just saw /dev/sda2 .. that's a device, you can't mount directly a device over the network you need to mount the device to a local folder on let's say X server, set up NFS and export that folder AND then mount it from Y server over the network.