I had settled the problem last time,with help.:)First of all, you must insmod ftp_conntrack(nat_ftp_conntrack....etc).The module work for processing the ftp connection.And then, you should bind ftp on 21port.The module only can track the21port by default.If you want to set other port,you must edit thesource.You may setup your rule to allow the ftp pass.Did your ftp work?:)
