Local AWS SSM session terminates instantly

Question

I'm trying to connect to my RDS instance via EC2 and SSM. I'm on an Apple silicon Mac, I'm using the default terminal. I'm using the following command line script for port forwarding:

aws ssm start-session \
 --target <ec2 instance id> \
 --profile <my local dev profile> \
 --document-name AWS-StartPortForwardingSessionToRemoteHost \
 --parameters '{"host":[<My RDS PSQL endpoint>],"portNumber": 
 ["5432"],"localPortNumber":["5432"]}' \
 --debug

Here is what I've done:

• Installed the SSM plugin
• Configured SSM in AWS
• Successfully started a session from the console.
• I have ran this command with no errors locally.

The issue is when I run the above command locally, nothing happens. Then I look at the console, and a session has started. However, it is terminated after about 20 seconds. Every time. I read you're supposed to get a message like this

Starting session with SessionId: Jane-Roe-07a16060613c408b5

But I get no output and the debug printouts don't have any useful possible errors or reason for session termination. Any idea how to make this work?

Answer 1

Just ran into this exact situation, make sure you have the session-manager-plugin installed in your AWS CLI.