SMARTHOST CONFIGURATION USING SENDMAIL + CYRUS - SASL

The complete step by step configuration is available here.

SMART HOST SECTION : Here we install sendmail and sendmail-cf from the RPM. Then we modify the sendmail.mc file to incorporate some additional features not available by default. The following files are relevant : 

• genericstable
• dgenericstable
• authinfo.txt
• service.switch

RELAYING SERVER SECTION: Here we install the cyrus-sasl. First we have to make it. Then we have to make sendmail after making relevant changes in the site.config.m4. Modify the sendmail.mc file. Then Build sendmail. Create users using saslpassword. Also create users who would be sending files to outside world.  

MAIN DNS SERVER SECTION:

isl.named.rev:

$TTL 86400
@ IN SOA islbom1.utiisl.co.in. root.islbom1.utiisl.co.in.
(
2003080701 ; serial
300 ; Refresh
60 ; Retry
1209600 ; expire
43200) ; Minimum
IN NS islbom1.utiisl.co.in.
IN NS islbom2.utiisl.co.in.
20 IN PTR islbom1.utiisl.co.in.
18 IN PTR islbom2.utiisl.co.in. 

isl.named:

$TTL 86400
@ IN SOA islbom1.utiisl.co.in. root.islbom1.utiisl.co.in.
(
2003080701 ; serial
300 ; Refresh
60 ; Retry
1209600 ; expire
43200) ; Minimum
NS islbom1.utiisl.co.in.
NS islbom2.utiisl.co.in.
MX 10 islbom1
gsd MX 10 islbom2
localhost A 127.0.0.1
islbom1 A 203.94.228.20
islbom2 A 203.94.228.18
www IN CNAME islbom1.utiisl.co.in.
www.pancard IN CNAME islbom2.utiisl.co.in.