Port 25 SMTP external access

Posted August 18, 2015 11.6k views
UbuntuServer OptimizationEmailDigitalOceanSystem Tools

How can I unblock port 25 for external access? Does digitalocean block this port by default?

These answers are provided by our Community. If you find them useful, show some love by clicking the heart. If you run into issues leave a comment, or add your own answer to help others.

Submit an Answer
3 answers

On some new accounts port 25 may be blocked by default. This block can be lifted as long as your account has no history of abuse by opening a ticket with our support team from the control panel or by emailing support@. They will verify for you whether a block is in place and can remove it if one is present.

Port 25 Direct Injection is the ability to communicate with a mail server directly not using MX records. This happens when access to Port 25 for SMTP traffic is not restricted. Best email security practice is to restrict Port 25 to only accept from trusted IP’s.

Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0* LISTEN 6427/master

How to set this restriction properly ?

Hello all,

It is possible that port 25 is closed for new accounts. This is something we have been doing to reduce spam on our network. Please do not think that we are accusing you of sending spam, it is more that we simply cannot accurately determine who is going to send it.

Stopping spam is a constant fight, so we have implemented some restrictions on newer accounts. To qualify for the ability to send out email, we do require accounts to wait 60 days before we can look into removing the restriction. Once your account has reached 60 days of stable use, please do reach back out to us so we can look into this for you.

Hope that helps!