[lug] postfix localhost only

[karl horlen]

i searched the net hi and low.  not finding what i want.  

i want to configure a postfix on a server to receive and deliver local mail only from and to virtual accounts on the same box.  i don't want it to relay mail destined for any domain outside the box.  and i don't want it to accept incoming mail on any external interface or domain outside the box.  

i found out how to do the virtual accounts online.  i can't find anything that directly addresses what i want to do.  i've found recipes for a bunch of more complex scenarios.  based upon that research, it looks like there are about 3-5 config lines that are probably required to do this but i'm not sure i'm getting it right.

my rationale for doing this is that if i connect squirrelmail to this postfix configuration, i can allow a close knit group of friends to send private mail back and forth to eachother.  since the server interfaces aren't opened up to send or receive mail, i don't have to worry about spam and a bunch of related extra stuff.  sure it's limited in functionality, but it fits the bill for what i want to do.

the general theory is that mail never leaves the server.  although this isn't perfectly true, if squirrelmail is config'd for ssl, it will be encrypted which satisfies the portion of the mail that travels over the net.  otherwise, all mail communication lives on that single server.

thanks