IP Security Feature in SMTP services

Overview

The IP Security feature in SMTP adds an extra layer of protection by restricting SMTP access to specific IP addresses. This ensures that only authorized IPs can send emails through your SMTP server, safeguarding your account from unauthorized access and misuse.

Benefits of IP Security in SMTP

• Enhanced Security: Restricts access to only approved IP addresses, reducing the risk of unauthorized use.

• Control Over Access: Allows you to manage and monitor which IP addresses are permitted to use your SMTP service.

• Protection from Spam: Prevents malicious users from sending spam or fraudulent emails from your SMTP account.

Steps to Configure IP Security in SMTP

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1) Login to your MSG91 account and navigate to the Email section.

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2) In the Domain Settings, click on SMTP credentials, then enable IP Security.

Note: By default, IP security for SMTP services will remain disabled.

3) Click on Add IP, enter the IP address and a description, then click Add. The whitelisted IP will now be visible in the IP column along with the description.

Additional Information:

• IP whitelisting can be done using CIDR Notation. Refer to this article for more details on CIDR.

• If you have multiple domains, you must whitelist the IPs for each domain individually.

• Supports both IPv4 and IPv6 for IP whitelisting.

Error Handling:

Once IP Security is configured, SMTP email requests will only be delivered from whitelisted IPs. Any request from an unknown IP will fail with error code 535 (IP not whitelisted). You can review this in real-time response as well as by checking the Failed Logs under MSG91 > Email > Failed Logs.