I took it that this was what was happening: postfix was adding the subnet that my ADSL IP address was on to the list of trusted hosts. Both mynetworks_style and mynetworks were commented out, as per (my) default postfix configuration. So the default values would be mynetworks_style = subnet and mynetworks = "the various subnets that the local machine is in". This appears to be confirmed by the fact that specifying "mynetworks = 192.168.1.0/24, 127.0.0.0/8, my.fixed.IP.address/32" seems to have stopped this happening.
urgh, how does your adsl work? are you bridged? many adsl (including mine) use ppp, so the dialup interface is a /32. Reading your mail it dawned on me that there are many providers that might bridge instead of using ppp (especially in residential area networks cabled in fiber).
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P.S. I just tried running the same postconf command as you on my main.cf.rpmnew. This gives mynetworks as 127.0.0.0/8, same as you, although mynetworks is commented out. The same command on my main.cf gives mynetworks of "127.0.0.0/8, 192.168.1.0/24, my.fixed.IP.address", whether or not mynetworks is commented out. The difference appears to be inet_interfaces, which is set to localhost in the rpmnew file, but is commented out (and therefore "= all") in my actual main.cf. Maybe an older configuration, I don't know. I certainly haven't changed it in a long time - I didn't even think about this setting. Would it work as a mail server sending and receiving mail for a local network if inet_interfaces were set to localhost?
No, that's the point mandrake postfix in default configuration does not allow receiveing mail, so it would not allow you to forward mail coming from local network. Oh, this setting was added in mandrake 9.0 in case you wondered.
maybe we should change default postfix main.cf forcing mynetwork_style=host, so there would be two step to open a relay 1) change inet_interfaces to be able to receive mail 2) set mynetworks (comments should advise to leave mynetworks_style alone) This makes sense, since there are people who don't want to relay mail, but might want to receive it.
Regards, L.
P.S. Since we are speaking of postfix default setup, it seems that Vietse has strong feelings against chrooting postfix by default. Simon J. Mudd provided a script in his rpms to add/remove the chroot by user request. I personally never had a problem with chroots, but what is the feeling around here?
regards, L.
--
Luca Berra -- [EMAIL PROTECTED]
Communication Media & Services S.r.l.
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