Amazon ec2 Public DNS not working

With reference to this question: How do I access my public DNS on Amazon's EC2

If I configure my security groups acccording to Windows web platform firewall rules then is there an issue? Because when I did that I couldn't access the Public DNS on web browser.

  1. My security group is default and inbound rules are HTTP, RDP ,SMTPS, ICMP.

  2. My instance type is t1.micro webmatrix hosting server with default security group.

  3. My windows firewall is active for domain ,public and private profile.

  4. I am not sure about this point. Its HTTP port 80 as shown in my security group.

I am new to Amazon EC2 and this is really urgent.


If you are using the instance as a public DNS server then you will need to have UDP port 53 open in the instance firewall (if it has one) and in the Security Group that the instance is in.

Go to your AWS management console and Select EC2. Then Under navigation click on Network & Security -> Security Groups

Security Groups

In the Security Groups Pane select the group your instance is in (most likely default)

Select Group

Then In the lower pane click Create new Rule and select DNS

Select DNS

Then click Add Rule followed by `Apply Rule Changes. The EC2 security group will now allow DNS queries to your instance.


For developers working on Windows VPS, please ensure to add a custom rule for the specific port at which the server is running in Incoming Firewall rules. After adding custom rules for HTTP(port 8080), DNS(port 53) in Amazon EC2 security.

I had added incoming custom rule for port 8080 as my Apache tomcat server was running at port 8080 in Windows VPS.

Control Panel --->Windows Firewall ---> Advanced Settings Inbound Rules ---> Create a new rule and give the port at which the server is running