Strange DNS Problem?

[Bigdakine]

Hi Folks,

  I have this weird problem. I'm testing the fallover capability of our
mailserver. I simply shutdown sendmail on the mail server, and start it in
server mode on a backup mail server. The odd thing is that when I send mail
from outside my domain to my domain, this is handled correctly. Running
sendmail in verbose mode, I see it try the primary mailserver first, and the
deliver the mail to the seconday mail server. Well, I gues that isn't odd. The
odd part is, is that when I send email to other users within the domain, from
within the domain, it chokes. It tries to deliver to "mailhost" and when that
fails, doesn't attempt to deliver to the secondary which is akala. 

mailhost is given a cname record is it is an alias for luna, the primary mail
server


My forward file looks like:

; BIND version named LOCAL-020930.002038 Mon Sep 30 00:20:38 GMT 2002
; BIND version root at akala:/opt/share/bind/src/bin/named
; zone 'XXXX.COMM.GOV'   last serial 2004022920
; from 150.70.102.225:53 (local 150.70.102.156) using AXFR at Sun Feb 29
20:18:59 2004
; TSIG verified: key luna-akala.
$ORIGIN COMM.GOV.
XXXX    86400   IN      SOA     luna.XXXX.COMM.GOV. stuart.XXXX.NOAA.GOV. (
                2004022921 10800 3600 604800 86400 )
        86400   IN      NS      LUNA.XXXX.COMM.GOV.
        86400   IN      NS      AKALA.XXXX.COMM.GOV.
        86400   IN      NS      HALE.XXXX.COMM.GOV.
        86400   IN      NS      NWRNS.COMM.GOV.
        86400   IN      NS      SERNS.COMM.GOV.
        86400   IN      NS      MERNS.COMM.GOV.
        86400   IN      NS      MWRNS.COMM.GOV.
        2419200 IN      MX      5 LUNA.XXXX.COMM.GOV.
        2419200 IN      MX      10 AKALA.XXXX.COMM.GOV.
        2419200 IN      MX      15 HALE.XXXX.COMM.GOV.
$ORIGIN XXXX.COMM.GOV.
LUNA    2419200 IN      MX      5 LUNA.XXXX.COMM.GOV.
        2419200 IN      MX      10 AKALA.XXXX.COMM.GOV.
        2419200 IN      MX      15 HALE.XXXX.COMM.GOV.
        2419200 IN      A       150.70.102.225
AKALA   2419200 IN      MX      5 LUNA.XXXX.COMM.GOV.
        2419200 IN      MX      10 AKALA.XXXX.COMM.GOV.
        2419200 IN      MX      15 HALE.XXXX.COMM.GOV.
        2419200 IN      A       150.70.102.156
KUKINI  2419200 IN      A       150.70.102.143
LEHUA   2419200 IN      A       150.70.102.145
MOLOKINI        2419200 IN      A       150.70.102.158
MIKI    2419200 IN      A       150.70.102.224
MONKU   2419200 IN      A       150.70.102.157
YANKEES 2419200 IN      A       150.70.102.147
NENE    2419200 IN      A       150.70.102.227
HALE    2419200 IN      MX      5 LUNA.XXXX.COMM.GOV.
        2419200 IN      MX      10 AKALA.XXXX.COMM.GOV.
        2419200 IN      MX      15 HALE.XXXX.COMM.GOV.
        2419200 IN      A       150.70.102.221
LULU    2419200 IN      A       150.70.102.219
HAWAII  2419200 IN      A       150.70.102.149
TYRKER  2419200 IN      A       150.70.102.140
MAILHOST        2419200 IN      CNAME   LUNA.XXXX.COMM.GOV.
PILIKIA 2419200 IN      A       150.70.102.222
Q730R   2419200 IN      A       150.70.102.160
KONA    2419200 IN      A       150.70.102.152
EW      2419200 IN      A       150.70.102.169
HOLO    2419200 IN      A       150.70.102.226
KAKU    2419200 IN      A       150.70.102.218
RAPANUI 2419200 IN      A       150.70.102.159
KAIAPELE        2419200 IN      A       150.70.102.136
EWA     2419200 IN      A       150.70.102.153

Some things were changed to protect the innocent..

Does anyone have any ideas on why local sendmail clients fail to deliver to the
backup mail server?

Yours,

Stuart
Dr. Stuart A. Weinstein
Ewa Beach Institute of Tectonics
"To err is human, but to really foul things up 
requires a creationist"