Re: [Exim] Exim Help

On Mon, 13 Aug 2001 21:00:01 -0700, John W Baxter wrote:

>At 15:45 -0600 8/13/2001, Aly Dharshi wrote:
>% nslookup 142.66.73.2
>Server: ...
>Address: ...
>
>*** ... can't find 142.66.73.2: Non-existent host/domain

you really should be using dig for this; nslookup is erratic on its
best days, and can be befuddled by NIS, NIS+, or /etc/hosts in ways
that will obscure what is going on with DNS.

>The "(failed to find host name from IP address)" part looks as if it were
>part of the error report, but it's more like "commentary" by Exim (I'm not
>going to accept this relay, and oh by the way the host has no name). At
>least in most places it appears...it isn't the cause of the rejection.

actually, it probably is. if exim is placed in the situation of
needing to do a reverse lookup, it may reject. for example:

if the following is set

host_reject_recipients=10.0.0.0/8:172.16.0.0/12:spam.source.com

then on connection from a host at ip 192.168.2.1, exim will do a
reverse lookup to see if 192.168.2.1 has the name spam.source.com
lack of working dns will cause the exim to reject the mail.

you avoid this by adding +allow_unknown at the start of the
host_reject_recipients line

richard