Services or capabilities described in Amazon Web Services documentation might vary by Region. To see the differences applicable to the China Regions, see Getting Started with Amazon Web Services in China (PDF).

Troubleshooting SSM Agent

If you experience problems running operations on your managed nodes, there might be a problem with Amazon Systems Manager Agent (SSM Agent). Use the following information to help you view SSM Agent log files and troubleshoot the agent.

SSM Agent is out of date

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.

View SSM Agent log files

SSM Agent logs information in the following files. The information in these files can also help you troubleshoot problems. For more information about SSM Agent log files, including how to turn on debug logging, see Viewing SSM Agent logs.

For Linux managed nodes, you might find more information in the messages file written to the following directory: /var/log.

Agent log files don't rotate (Windows)

If you specify date-based log file rotation in the seelog.xml file (on Windows Server managed nodes) and the logs don't rotate, specify the fullname=true parameter. Here is an example of a seelog.xml configuration file with the fullname=true parameter specified.

<seelog type="adaptive" mininterval="2000000" maxinterval="100000000" critmsgcount="500" minlevel="debug">
   <exceptions>
      <exception filepattern="test*" minlevel="error" />
   </exceptions>
   <outputs formatid="fmtinfo">
      <console formatid="fmtinfo" />
      <rollingfile type="date" datepattern="200601021504" maxrolls="4" filename="C:\ProgramData\Amazon\SSM\Logs\amazon-ssm-agent.log" fullname=true />
      <filter levels="error,critical" formatid="fmterror">
         <rollingfile type="date" datepattern="200601021504" maxrolls="4" filename="C:\ProgramData\Amazon\SSM\Logs\errors.log" fullname=true />
      </filter>
   </outputs>
   <formats>
      <format id="fmterror" format="%Date %Time %LEVEL [%FuncShort @ %File.%Line] %Msg%n" />
      <format id="fmtdebug" format="%Date %Time %LEVEL [%FuncShort @ %File.%Line] %Msg%n" />
      <format id="fmtinfo" format="%Date %Time %LEVEL %Msg%n" />
   </formats>
</seelog>

Unable to connect to SSM endpoints

SSM Agent must allow HTTPS (port 443) outbound traffic to the following endpoints:

SSM Agent won't work if it can't communicate with the preceding endpoints, even if you use Amazon provided Amazon Machine Images (AMIs) such as Amazon Linux 2 or Amazon Linux 2023. Your network configuration must have open internet access or you must have custom virtual private cloud (VPC) endpoints configured. If you don't plan on creating a custom VPC endpoint, check your internet gateways or NAT gateways. For more information about how to manage VPC endpoints, see Step 2: Create VPC endpoints.