Sendmail Help

[Paul Howarth]

Dan Track wrote:
> On 5/22/06, Paul Howarth <paul at city-fan.org> wrote:
>> Dan Track wrote:
>> > Hi
>> >
>> > I'm trying to sendmail from a client. The domain has four mx records
>> > for example.com, mx1 (weight 10),mx2 (weight 5),mx3 (weight 1),mx4
>> > (weight 2).
>> >
>> > The problem I have is that when sending mail, the client always tries
>> > to access mx1. And since this isn't configured the connections gets
>> > refused. Can someone please explaing to me why it doesn't try any of
>> > the others first, given the weighting order?
>> >
>> > This is a standard sendmail install without any configuration changes.
>> >
>> > Thanks for your help in advance
>>
>> Please post the output of "dig example.com mx" when run on the client.
>>
> 
> 
> Hi
> 
> Thanks for your help.
> 
> Dig result from the client is:
> 
> dig example.com mx
> 
> ; <<>> DiG 9.2.4 <<>> example.com mx
> ;; global options:  printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 39743
> ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 2, ADDITIONAL: 6
> 
> ;; QUESTION SECTION:
> ;example.com.                        IN      MX
> 
> ;; ANSWER SECTION:
> example.com.         3600    IN      MX      5 mars.l3.example.com.
> example.com.         3600    IN      MX      10 mars.gs.example.com.
> example.com.         3600    IN      MX      1 cluster-b.example.com.
> example.com.         3600    IN      MX      2 cluster-f.example.com.
> 
> ;; AUTHORITY SECTION:
> example.com.         3600    IN      NS      dns0.example.com.
> example.com.         3600    IN      NS      dns1.example.com.
> 
> ;; ADDITIONAL SECTION:
> cluster-b.example.com. 602261 IN    A       y.y.y.190
> cluster-f.example.com. 602261 IN    A       z.z.z.190
> mars.l3.example.com. 300     IN      A       x.x.x.25
> mars.gs.example.com. 3600    IN      A       k.k.k.98
> dns0.example.com.    3600    IN      A       x.x.x.26
> dns1.example.com.    3600    IN      A       k.k.k.98
> 
> ;; Query time: 4 msec
> ;; SERVER: x.x.x.98#53(x.x.x.98)
> ;; WHEN: Mon May 22 13:56:46 2006
> ;; MSG SIZE  rcvd: 278
> 
> 
> So when sending mail it always goes to:
> 10 mars.gs.example.com.
> 
> Any idea?

OK, what's the output of (on the client):

# echo /mx example.com | sendmail -bt

It's much easier to diagnose these issues when real domain names and IP 
addresses are used.

Are the "A" records associated with all of the mail servers correct? Do 
they refer to real, routable addresses, or RFC 1918 private addresses? 
Can you reach all of those servers using "telnet cluster-b.example.com. 
smtp" etc.?

Paul.