ec2connect

In June 2019, AWS released EC2 Instance Connect - a way of authenticating SSH sessions using AWS IAM policies. This massively improves security by removing the need for sharing SSH private keys. It also improves reliability by removing the need for any workarounds to avoid sharing keys!

AWS did release an mssh tool, but it's not as nice as it could be. ec2connect improves upon it:

• Doesn't require Python to be installed. Single binary available for Mac, Linux and Windows.
• Doesn't require a new command to be remembered - just ssh ec2-user@host as normal.
• Integrates nicely with every other tool - any tool that relies on SSH (e.g. git) will work out of the box due to the above.

Installation

• Mac: brew install glassechidna/taps/ec2connect
• Windows: scoop bucket add glassechidna https://github.com/glassechidna/scoop-bucket.git; scoop install ec2connect
• Otherwise get the latest build from the Releases tab.

Usage

On first time usage, run ec2connect setup. This sets up your SSH configuration to use ec2connect to connect to your instances. You only need to run this once.

Now, connect to your instances using ssh <user>@<instance id>. For example:

# regular ssh connection
ssh ec2-user@i-000abc124def

# in a different region
AWS_REGION=us-west-2 ssh ec2-user@i-000abc124def

# with a profile
AWS_PROFILE=mycompany ssh ec2-user@i-000abc124def

# with port-forwarding. the possibilities are endless!
ssh -L 2375:127.0.0.1:2375 ec2-user@i-000abc124def

Known issues

Right now this tool only works with SSH public keys that are stored on disk or in an SSH agent. What that means in effect is that you can't pass in an identity using ssh -i <pemfile>.