Mail realying using DNS !

[Veeraraju_Mareddi]

Dear All,

I have one Internal mail server, which is configure to deliver mail based on
DNS lookup. In Internal DNS serverI wanna add MX records for all internet
domains to a mailgateway so that all SMTP mails go to
mailgateway.mydomain.com. Mailgateway will deliver mails to actual outside
world. This is one type of relaying.

How can I do this ? Is there any method we can add MX records ,which will be
answered each time when MX is queried for any domain.

Thank you.

Warm Regards,

Veeraraju_Mareddi
Networks & Systems
TSR Towers,4th Floor
Tel:3306767 ext:7455
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