Bufffalo Terrastation TS-X4.0TS - difficulty setting up replication. Advice please.

[Number6]

We've just bought 2 x Terrastations for use as backup devices. The plan is to use one device as the primary backup and to replicate it to a second identical unit.

 

Both units are attached to the same network as AD devices.

 

Can't get the replication set up.

 

The manual says to go to the web admin screen, log into the first box, navigate to System > Backup > Replication, click add and select the source and target from the drop down boxes. This is where we fail. The source folders show up but the target dropdown either hangs on "loading" or displays a blank box.

 

I've also tried adding the IP of the second unit to the list of "off-subnet" units but that doesn't help.

 

The manual is less than clear, in the preamble for replication setup it states that to set up replication then LAN port 2 on each machine should be connected; I'm unclear if that means just for the setup phase or to enable replication they should be permanently connected? But anyway I've tried that option as well with the same non-result.

 

Has anyone successfully set replication up on these devices and can offer me some advice? I'm seriously head-scratching right now.