MX Record Priority Not Working

  • Thread starter Thread starter Simon
  • Start date Start date
S

Simon

Hi,

I have two relay servers.
The MX Records have priorities of 10 and 100

However I see that emails still comes in huge numbers to the relay server
with lower MX record priority.

Any ideas?

Cheers
~Simon
 
In
Simon said:
Hi,

I have two relay servers.
The MX Records have priorities of 10 and 100

However I see that emails still comes in huge numbers to
the relay server with lower MX record priority.
Click to expand...

Mail will go to the mail server with 100 priority any time the mail server
with 10 priority is not available. I see this as more of a mail server
problem if you main server is unavailable more than you think it should be.
It has nothing to do with the MX record, you could set the priority to 1000
and it will still get just as much mail as it does now.
 
Thanks Kevin.

The relay server with 10 priority runs all the time and is on a good
internet link.
However the traffic pattern on the mail server with 100 priority is more of
Spam in nature.
Is it possible that Spammers target specific mail servers and ignore the MX
record priority.

~Cheers
Simon
 
Yes. This is a common thing that spamware does. The reasoning for it I
believe is that spammers figure the initial mail server has
anti-spam/antivirus software running on it. Alot of people misconfigure
their mail setups to still allow mail from anyone to their lower
priority/higher mx mail servers, which don't always have the anti software
running on it. So they try to bypass the filters that way.
 
The relay server with 10 priority runs all the time and is on a
good internet link. However the traffic pattern on the mail server
with 100 priority is more of Spam in nature. Is it possible that
Spammers target specific mail servers and ignore the MX
record priority.
Click to expand...

Yes, it's possible... and it happens :-) that said, if you want to
perform some kind of "load balance" (well round-robin would
be better) between the two servers, just set both MX records
to the same priority (e.g. 10) this way sender SMTP servers
will pick either MX and in any case you'll still have "fallback"
config, since in case one of the MX servers goes "down" the
other will still serve as needed

--

* Andrea "ObiWan" Zenobi

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