[COFF] 3b2/400 inbound connectivity

I have a 3b2/400 emulator running Unix V r3 fine, but I have two questions. Unix is set up with IP 10.0.2.15 I can telnet off it great *but* can not telnet into it. Is there a step I am missing? In the sim ini file I have set: set NI enabled attach NI nat: Someone suggested: attach nat:tcp=2323:10.0.2.15:23,tcp=2121:10.0.2.15:21 but that did not work. This is what I get at boot time: NAT args: NAT network setup: gateway =10.0.2.2/24(255.255.255.0) DNS =10.0.2.3 dhcp_start =10.0.2.15 Protocol[State] FD Source Address Port Dest. Address Port RecvQ SendQ /home/ken/MYSIMS/System-V-r3/boot.ini-51> attach NI nat: %SIM-INFO: Eth: opened OS device nat: Thanks, Ken -- WWL 📚