Setup another DNAS and have it relay the main DNAS.
From the DNASs sc_serv.ini/conf configuration file:
; RelayPort and RelayServer specify that you want to be a relay server.
; Relay servers act as clients to another server, and rebroadcast.
; Set RelayPort to 0, RelayServer to empty, or just leave these commented
; out to disable relay mode.
Set relayport of the secondary DNAS to the portbase of the main DNAS.
Set relayserver of the secondary DNAS to the ip of the main DNAS.
Also, don't forget to remove the comment designator ( ; ) from the front of both lines after making the changes then restart the DNAS.