SMTP Server Q&A

How SMTP server works

Agenda

• How SMTP server works?• Setting up for receiving• Setting up for sending• What is RBL (DNSBL) and how it works?• How SMTP server checks incoming message?• Avoiding spam traps

How SMTP server works

Setting up server for receiving

1. Set up SMTP server2. Set up static IP on the server computer3. Check your routers to make sure port 25 is

open4. Make sure your external (router) IP is static5. Point all IP addresses for MX records of all

domains you want to control to your static IP address

1. Static IP on server PC

2. Check external routers

4. Set up DNS zone file with MX record

Setting up server for sending

1. Perform 1-5 above2. Add reverse DNS (PTR) lookup (ask your ISP)3. Add SPF4. Make sure your external IP is not listed in RBL

What is reverse DNS check

Check your reverse DNS

How SPF records are checked

Setting up SPF records

How RBL verification works

How to check your IP in RBL servers

SMTP server checks