Am Mi, den 14.07.2004 schrieb Gene Heskett um 19:15: > I was under the impression that it was a localmail problem all along, > (like amanda trying to send root a message) in which case mail sent > to AAA, must have the AAA defined in the hosts file, or as an entry > in a dns record in some machine known to AAA. The point being that > if AAA is unknown, then the dns of record (from resolv.conf) is going > to be consulted for the resolution of the address represented by AAA. > > At least thats how I've understood it for over a decade now. > > Sorry if I was mistaken, and please educate me if you have the time. > Cheers, Gene Hi Gene, I am myself a current learner and far from "knowing that all". Let me try to move through the things from a different route. By default first the /etc/hosts file is asked for name resolution. That is defined in the /etc/host.conf with content "order hosts,bind". If the hosts file does not hold the information then a nameserver will be asked. These are defined in the /etc/resolv.conf. The possible "search foo" syntax in there says: if the given name to be looked up is not a FQDN then add the given foo domain to the name first for lookups. The /etc/hosts file maps IP addresses to FQDN (fully qualified domain names) and their short names to IP addresses. In Philippe's case the AAA is no short name but his internal local domain name. But the hosts file does not resolv domain names, it resolves fully qualified domain names, which are hostname + domain name. In his case P4.AAA is the FQDN and P4 the short name. Speaking about mail it is correct that mail sent to outside must come from a host with a resolvable FDQN (must, because most MTAs reject unresolvable relays to prevent SPAM). Host internally sent mail uses localhost or as FQDN localhost.localdomain as relay and lookup that in the hosts file (therefor you see the comment in there). Of course, if Philippe did give his Sendmail a hostname which is not resolvable, neither by the hosts file nor a DNS, his MTA will not work proper. So I requested him to paste the results from "sendmail -bt -d0.12 < /dev/null" to get closer to his configuration. Alexander -- Alexander Dalloz | Enger, Germany | GPG key 1024D/ED695653 1999-07-13 Fedora GNU/Linux Core 2 (Tettnang) Athlon CPU kernel 2.6.6-1.435.2.3.uml Serendipity 19:46:14 up 1 day, 17:28, load average: 0.56, 0.29, 0.21
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