aws-ssm-tools

aws-ssm-tools - AWS System Manager Tools

Helper tools for AWS Systems Manager: ec2-session, ec2-ssh and ssm-tunnel, and for ECS Docker Exec: ecs-session

Scripts included

• ec2-session (formerly ssm-session)

  Wrapper around aws ssm start-session that can open  SSM Session to an instance specified by Name or IP Address.

  It doesn't need user credentials or even sshd running on the instance.

  Check out SSM Sessions the easy way for an example use.

  Works with any Linux or Windows EC2 instance registered in SSM.

• ecs-session

  Wrapper around aws ecs execute-command that can run a command or open an interactive session to an Exec-enabled ECS container specified by the service, name, IP address, etc.

  It doesn't need user credentials or sshd running on the container, however the containers must be configured to allow this access.

  Check out Interactive shell in ECS Containers for an example use.

• ec2-ssh (formerly ssm-ssh)

  Open an SSH connection to the remote server through Systems Manager without the need for open firewall or direct internet access. SSH can then be used to forward ports, copy files, etc.

  Unlike ssm-tunnel it doesn't create a full VPN link, however it's in some aspects more versatile as it can be used with rsync, scp, sftp, etc.

  It works with any client that can run SSH (including Mac OS-X) and doesn't require a special agent on the instance, other than the standard AWS SSM agent.

  Also supports pushing your SSH key to the instance with --send-key (aka EC2 Instance Connect, although that's an odd name for this function).

• ssm-tunnel

  Open IP tunnel to the SSM instance and to enable network access to the instance VPC. This requires ssm-tunnel-agent installed on the instance.

  Works with Amazon Linux 2 instances and probably other recent Linux EC2 instances. Requires Linux on the client side - if you are on Mac or Windows you can install a Linux VM in a VirtualBox.

  Requires ssm-tunnel-agent installed on the instance - see below for instructions.

Usage

1. List instances available for connection

   ~ $ ec2-session --list
   i-07c189021bc56e042   test1.aws.nz       test1        192.168.45.158
   i-094df06d3633f3267   tunnel-test.aws.nz tunnel-test  192.168.44.95
   i-02689d593e17f2b75   winbox.aws.nz      winbox       192.168.45.5    13.11.22.33
   

   If you're like me and have access to many different AWS accounts you can select the right one with --profile and / or change the --region:

   ~ $ ec2-session --profile aws-sandpit --region us-west-2 --list
   i-0beb42b1e6b60ac10   uswest2.aws.nz     uswest2      172.31.0.92
   

   Alternatively use the standard AWS environment variables:

   ~ $ export AWS_DEFAULT_PROFILE=aws-sandpit
   ~ $ export AWS_DEFAULT_REGION=us-west-2
   ~ $ ec2-session --list
   i-0beb42b1e6b60ac10   uswest2.aws.nz     uswest2      172.31.0.92
   

2. Open SSM session to an instance:

   This opens an interactive shell session over SSM without the need for a password or SSH key. Note that by default the login user is ssm-user. You can specify most a different user with e.g. --user ec2-user or even --user root.

   ~ $ ec2-session -v test1 --user ec2-user
   Starting session with SessionId: botocore-session-0d381a3ef740153ac
   [ec2-user@ip-192-168-45-158] ~ $ hostname
   test1.aws.nz
   
   [ec2-user@ip-192-168-45-158] ~ $ id
   uid=1000(ec2-user) gid=1000(ec2-user) groups=1000(ec2-user),...
   
   [ec2-user@ip-192-168-45-158] ~ $ ^D
   Exiting session with sessionId: botocore-session-0d381a3ef740153ac.
   ~ $
   

   You can specify other SSM documents to run with --document-name AWS-... to customise your session. Refer to AWS docs for details.

3. Open SSH session over SSM with port forwarding.

   The ec2-ssh tool provides a connection and authentication mechanism for running SSH over Systems Manager.

   The target instance does not need a public IP address, it also does not need an open SSH port in the Security Group. All it needs is to be registered in the Systems Manager.

   All ssh options are supported, go wild. In this example we will forward port 3306 to our MySQL RDS database using the standard -L 3306:mysql-rds.aws.nz:3306 SSH port forwarding method.

   ~ $ ec2-ssh ec2-user@test1 -L 3306:mysql-rds.aws.nz:3306 -i ~/.ssh/aws-nz.pem
   [ec2-ssh] INFO: Resolved instance name 'test1' to 'i-07c189021bc56e042'
   [ec2-ssh] INFO: Running: ssh -o ProxyCommand='aws ssm start-session --target %h --document-name AWS-StartSSHSession --parameters portNumber=%p' i-07c189021bc56e042 -l ec2-user -L 3306:mysql-rds.aws.nz:3306 -i ~/.ssh/aws-nz.pem
   OpenSSH_7.6p1 Ubuntu-4ubuntu0.3, OpenSSL 1.0.2n  7 Dec 2017
   ...
   Last login: Sun Apr 12 20:05:09 2020 from localhost
   
      __|  __|_  )
      _|  (     /   Amazon Linux 2 AMI
     ___|\___|___|
   
   [ec2-user@ip-192-168-45-158] ~ $
   

   From another terminal we can now connect to the MySQL RDS. Since the port 3306 is forwarded from localhost through the tunnel we will instruct mysql client to connect to 127.0.0.1 (localhost).

   ~ $ mysql -h 127.0.0.1 -u {RdsMasterUser} -p
   Enter password: {RdsMasterPassword}
   Welcome to the MariaDB monitor.  Commands end with ; or \g.
   Server version: 5.6.10 MySQL Community Server (GPL)
   
   MySQL [(none)]> show processlist;
   +-----+------------+-----------------------+
   | Id  | User       | Host                  |
   +-----+------------+-----------------------+
   |  52 | rdsadmin   | localhost             |
   | 289 | masteruser | 192.168.45.158:52182  | <<< Connection from test1 IP
   +-----+------------+-----------------------+
   2 rows in set (0.04 sec)
   

4. Use rsync with ec2-ssh to copy files to/from EC2 instance.

   Since in the end we run a standard ssh client we can use it with rsync to copy files to/from the EC2 instance.

   ~ $ rsync -e ec2-ssh -Prv ec2-user@test1:some-file.tar.gz .
   some-file.tar.gz
        31,337,841 100%  889.58kB/s    0:00:34 (xfr#1, to-chk=0/1)
   sent 43 bytes  received 31,345,607 bytes  814,172.73 bytes/sec
   total size is 31,337,841  speedup is 1.00
   

   We can also select a different AWS profile and/or region:

   ~ $ rsync -e "ec2-ssh --profile aws-sandpit --region us-west-2" -Prv ...
   

   Alternatively set the profile and region through standard AWS environment variables AWS_DEFAULT_PROFILE and AWS_DEFAULT_REGION.`

5. Create IP tunnel and SSH to another instance in the VPC through it.

   We will use --route 192.168.44.0/23 that gives us access to the VPC CIDR.

   ~ $ ssm-tunnel -v tunnel-test --route 192.168.44.0/23
   [ssm-tunnel] INFO: Local IP: 100.64.160.100 / Remote IP: 100.64.160.101
   00:00:15 | In:  156.0 B @    5.2 B/s | Out:  509.0 B @   40.4 B/s
   

   Leave it running and from another shell ssh to one of the instances listed with --list above. For example to test1 that's got VPC IP 192.168.45.158:

   ~ $ ssh ec2-user@192.168.45.158
   Last login: Tue Jun 18 20:50:59 2019 from 100.64.142.232
   ...
   [ec2-user@test1 ~]$ w -i
    21:20:43 up  1:43,  1 user,  load average: 0.00, 0.00, 0.00
   USER     TTY      FROM             LOGIN@   IDLE   JCPU   PCPU WHAT
   ec2-user pts/0    192.168.44.95    21:20    3.00s  0.02s  0.00s w -i
                     ^^^^^^^^^^^^^
   [ec2-user@test1 ~]$ exit
   Connection to 192.168.45.158 closed.
   ~ $
   

   Note the source IP 192.168.44.95 that belongs to the tunnel-test instance - our connections will appear as if they come from this instance. Obviously the Security Groups of your other instances must allow SSH access from the IP or SG of your tunnelling instance.

All these tools support --help and a set of common parameters:

--profile PROFILE, -p PROFILE
                    Configuration profile from ~/.aws/{credentials,config}
--region REGION, -g REGION
                    Set / override AWS region.
--verbose, -v       Increase log level.
--debug, -d         Increase log level even more.

ec2-ssh only supports the long options to prevent conflict with ssh's own short options that are being passed through.

Standard AWS environment variables like AWS_DEFAULT_PROFILE, AWS_DEFAULT_REGION, etc, are also supported.

Installation

All the tools use AWS CLI to open SSM Session and then use that session to run commands on the target instance. The target instances must be registered in SSM, which means they need:

• connectivity to SSM endpoint, e.g. through public IP, NAT Gateway, or SSM VPC endpoint.
• EC2 instance IAM Role with permissions to connect to Systems Manager.

Follow the detailed instructions at Using SSM Session Manager for interactive instance access for more informations.

Install AWS CLI and session-manager-plugin

Make sure you've got aws and session-manager-plugin installed locally on your laptop.

~ $ aws --version
aws-cli/1.18.31 Python/3.6.9 Linux/5.3.0-42-generic botocore/1.15.31

~ $ session-manager-plugin --version
1.1.56.0

Follow AWS CLI installation guide and session-manager-plugin installation guide to install them if needed.

Note that ec2-ssh needs session-manager-plugin version 1.1.23 or newer. Upgrade if your version is older.

Register your instances with Systems Manager

Amazon Linux 2 instances already have the amazon-ssm-agent installed and running. All they need to register with Systems Manager is AmazonEC2RoleforSSM managed role in their IAM Instance Role and network access to ssm.{region}.amazonaws.com either directly or through a https proxy.

Check out the detailed instructions for more info.

Install SSM-Tools (finally! :)

The easiest way is to install the ssm-tools from PyPI repository:

sudo pip3 install aws-ssm-tools

NOTE: SSM Tools require Python 3.6 or newer. Only the ssm-tunnel-agent requires Python 2.7 or newer as that's what's available by default on Amazon Linux 2 instances.

Standalone ssm-tunnel-agent installation

Refer to README-agent.md for ssm-tunnel-agent installation details.

Alternatively it's also bundled with this package, you can take it from here and copy to /usr/local/bin/ssm-tunnel-agent on the instance. Make it executable and it should just work.

Other AWS Utilities

Check out AWS Utils repository for more useful AWS tools.

Author and License

All these scripts were written by Michael Ludvig and are released under Apache License 2.0.