About SSM Agent - AWS Systems Manager

About SSM Agent

AWS Systems Manager Agent (SSM Agent) is Amazon software that runs on Amazon Elastic Compute Cloud (Amazon EC2) instances, edge devices, and on-premises servers and virtual machines (VMs). SSM Agent makes it possible for Systems Manager to update, manage, and configure these resources. The agent processes requests from the Systems Manager service in the AWS Cloud, and then runs them as specified in the request. SSM Agent then sends status and execution information back to the Systems Manager service by using the Amazon Message Delivery Service (service prefix: ec2messages).

SSM Agent must be installed on each instance you want to use with AWS Systems Manager. Some Amazon Machine Images (AMIs) are configured to launch instances with SSM Agent preinstalled. (You can also configure a custom AMI to preinstall SSM Agent.) For more information, see Amazon Machine Images (AMIs) with SSM Agent preinstalled.

On other AMIs; AWS IoT Greengrass core devices; and on-premises servers, edge devices, and virtual machines in your hybrid environment, you must install the agent manually, as described in the following table.

Important

An updated version of SSM Agent is released whenever new capabilities are added to Systems Manager or updates are made to existing capabilities. Failing to use the latest version of the agent can prevent your managed node from using various Systems Manager capabilities and features. For that reason, we recommend that you automate the process of keeping SSM Agent up to date on your machines. For information, see Automating updates to SSM Agent. Subscribe to the SSM Agent Release Notes page on GitHub to get notifications about SSM Agent updates.

Operating system type SSM Agent installation
Linux SSM Agent is installed by default on Amazon Linux, Amazon Linux 2, SUSE Linux Enterprise Server (SLES) 12 and 15, Ubuntu Server 16.04, 18.04 LTS, and 20.04 base Amazon EC2 AMIs. You must manually install SSM Agent on other versions of Amazon EC2 for Linux, including non-base images. For more information, see Working with SSM Agent on EC2 instances for Linux.
macOS

SSM Agent is installed by default on macOS 10.14.6 (Mojave), 10.15.7 (Catalina), and 11.x (BigSur) AMIs for Amazon EC2. For more information, see Working with SSM Agent on EC2 instances for macOS.

Windows

Windows AMIs published before November 2016 use the EC2Config service to process requests and configure instances.

Unless you have a specific reason for using the EC2Config service or an earlier version of SSM Agent to process Systems Manager requests, we recommend that you download and install the latest version of the SSM Agent to each of your EC2 instances and managed instances in your hybrid environment. For more information, see Working with SSM Agent on EC2 instances for Windows Server.

Edge devices

Systems Manager supports the following types of edge devices:

  • AWS IoT Greengrass core devices

  • AWS IoT devices

  • Non-AWS IoT devices

Setup requirements differ based on the type of edge device. For more information, see Setting up AWS Systems Manager for edge devices.

On-premises servers and VMs

You must manually install SSM Agent on on-premises servers and virtual machines (VMs) in your hybrid environment. The SSM Agent download and installation process for these machines is different than the process used for Amazon EC2 instances. For more information, see the following topics: