If you want to view or convert AWS EC2 user data into something readable in a terminal , the common AWS CLI command is:

bash

aws ec2 describe-instance-attribute --instance-id i-xxxxxxxxxxxxxxxxx --attribute userData --output text --query "UserData.Value"

That returns the user data in base64 , so to decode it in a terminal you can do:

bash

aws ec2 describe-instance-attribute --instance-id i-xxxxxxxxxxxxxxxxx --attribute userData --output text --query "UserData.Value" | base64 --decode

If you are on Windows

You may need to decode with:

cmd

certutil -decode userData.txt decoded.txt

If you are setting user data when launching an instance

You can pass it directly with:

bash

aws ec2 run-instances --image-id ami-xxxx --count 1 --instance-type t2.micro --user-data file://my_script.txt

If you want, I can also give you the exact command for:

  • Linux terminal
  • Windows PowerShell
  • getting user data from a running EC2 instance