This is not a strictly samba problem, but i hope someone could help me: I have two NT4 server (PDC and BDC) on a subnet a.b.c.0/24 . I have a number of win2000 with some NT4, XP clients and some win2k and samba servers. All are happy whitin the subnet. For local policy i have four in an area that have some security concern so these are behind a linux gateway acring as a natting firewall. So this firewall is set that every host "inside the area" get a number by dhcp in 192.168.19.20 to 150.217.19.188 Only four machines (one NT4 and three win2k) have fixed address 192.168.19.194 to .197 . on the gateway there is an iptables as: -A PREROUTING -s a.b.c.0/255.255.255.0 -d a.b.c.194 -j DNAT --to- destination 192.168.19.194 -A POSTROUTING -s 192.168.19.194 -j SNAT --to-source a.b.c.194 I have added to the domain the four administrators` hosts [by just plugghing diretly to main network with a temporary number) This way for that 4 machines all ports are open. All service run smoothly except that if I try from one of such machines to login as a non local user or try to add permission for an user on the server the machines invariantly say that thy cannot access main server. i have also added in lmhosts the address of the PDC and BDC with #PRE #DOMLMYDOMAIN but no success. It seem that thse machines cannot validate to the server throught the natting firewall (that incidentally, does not firewall anything for those 4 address, jst shift the addresses both way !) Can you help me ???? -- Leonardo Boselli Nucleo Informatico e Telematico del Dipartimento Ingegneria Civile Universita` di Firenze , V. S. Marta 3 - I-50139 Firenze tel +39 0554796431 cell +39 3488605348 fax +39 055495333 http://www.dicea.unifi.it/~leo