Linux?
MasqueradeAddress tar3.net PassivePorts 4000 4029
sudo yum install proftpd-ldap
#LoadModule mod_ldap.c
LoadModule mod_ldap.c
LDAPServer 123.456.789.123:389 LDAPAuthBinds on LDAPBindDN "cn=administrator,dc=hogehoge,dc=net" "password" LDAPUsers "dc=hogehoge,dc=net" "(uid=%u)" LDAPGroups "dc=hogehoge,dc=net" "(&(gidNumber=%v)(status=valid))" LDAPSearchScope subtree