Email firewall settings
Email firewall settings are used to control and filter incoming and outgoing email traffic to and from your email server. Here are some common email firewall settings:
Incoming Email Settings:
- Port 25: This is the default port used for incoming email traffic. You can block or allow incoming email traffic on this port.
- Port 587: This is an alternative port used for incoming email traffic. You can also block or allow incoming email traffic on this port.
- SMTP Authentication: This setting allows you to require authentication for incoming email traffic. You can set it to "required", "optional", or "disabled".
- Sender IP Blocking: This setting allows you to block incoming email traffic from specific IP addresses or IP address ranges.
Outgoing Email Settings:
- Port 25: This is the default port used for outgoing email traffic. You can block or allow outgoing email traffic on this port.
- Port 587: This is an alternative port used for outgoing email traffic. You can also block or allow outgoing email traffic on this port.
- SMTP Authentication: This setting allows you to require authentication for outgoing email traffic. You can set it to "required", "optional", or "disabled".
- Recipient IP Blocking: This setting allows you to block outgoing email traffic to specific IP addresses or IP address ranges.
Additional Email Firewall Settings:
- Spam Filtering: This setting allows you to block or allow email traffic based on spam filtering rules.
- Virus Scanning: This setting allows you to scan incoming and outgoing email traffic for viruses and malware.
- Content Filtering: This setting allows you to block or allow email traffic based on specific content, such as keywords or attachments.
- Rate Limiting: This setting allows you to limit the number of emails that can be sent or received within a certain time period.
- Blacklisting: This setting allows you to block email traffic from specific IP addresses or domains that are known to be malicious.
Examples of Email Firewall Settings:
- Allow incoming email traffic on port 25:
iptables -A INPUT -p tcp --dport 25 -j ACCEPT
- Block outgoing email traffic to specific IP address:
iptables -A OUTPUT -p tcp --dport 25 -d 192.0.2.1 -j DROP
- Require SMTP authentication for incoming email traffic:
postfix -o smtpd_sasl_security_options=may
- Block email traffic with specific keywords:
spamassassin -r -i /path/to/email -k "keyword1 OR keyword2"
Note: The specific email firewall settings and commands may vary depending on your email server software and operating system.