One of my Postfix installs runs behind a NAT box. The host name for the local private IP is in the .local domain, not suitable for public use in SMTP sessions but suitable for trace fields. However, on IPv6, the host is a first-class citizen on the net and has its own host name.
Can I arrange it so that the SMTP client uses different names in the EHLO/HELO command based on the protocol (IPv4 or IPv6) I am connecting with? I do not want IPv6 servers to know my server as "natbox.mydomain", but "Bloodstone.mydomain". (natbox is the NAT box, anything could run behind that.) more generally: can I arrange it so that I can select the EHLO/HELO name based on the destination host and protocol? Then intra-domain communication can use a local domain name. Cheers, Sabahattin
