** Reply to message from riwanlky <[EMAIL PROTECTED]> on Mon, 07 Aug
2006 14:58:52 +0700
>I don't know if it is the right place to write about this problem.
>I am running OpenBSD 3.9, however it seem to me that my OpenBSD
>box always send a DNS query for:
>- email sending (from internal and external) I had tried to add in my
>resolv.conf to use nameserver localhost. So that @mcojaya.com
>will not go to other DNS server for query. I use /etc/hosts to add
>127.0.0.1 mcojaya.com
>I have problem that when the internet is down, my local users were
>not able to send email because of DNS query check.
>- nagios. I use check_ping, and it seem that it will always query
>DNS for every ip address (host) that I setup to check_ping.
>
>I did not modify any inetd.conf
Sending email requires more than just an IP address. When sending a
message to <user>@<domain.example>, the mailer first checks where it
should be sent by looking for an 'MX' (Mail eXchanger) record for
<domain.example> -- and 'MX' records can only be suppied via DNS. The
typical setup is something like:
domain.example IN MX 10,mail-server.domain.example
mail-server.domain.example IN A 192.168.13.57
So if you want this to work when your internet connection is down you
need to either set up your own DNS server (it's not all that hard, but
is certainly not trivial) or find a mailer (if one exists) that does
some special hackery to avoid DNS queries for locally-addressed
messages.
Dave
--
Dave Anderson
<[EMAIL PROTECTED]>
