PHP Agent cannot connect to AppDynamics Controller – "ConfigChannel could not send config request"

[LASALEM]

Hello AppDynamics Support,

We are experiencing a persistent issue integrating the PHP Agent on a Red Hat 9.5 server running PHP 8.3. Below are the technical details and steps we've already taken.

 Technical Information

• PHP Agent version: 24.11.0.1340

• PHP version: 8.3

• OS: Red Hat Enterprise Linux 9.5

• Apache MPM: event

• Controller:xxx:443

• HTTP Proxy: xxx:3128

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 Problem Description

The agent initializes properly and correctly detects all necessary settings (controller host, account name, node, etc.).

However, the following error is always present in the logs:

[config.ConfigChannel] could not send config request

This prevents the agent from registering or communicating with the controller.

Troubleshooting Steps Already Taken

• controller-info.xml file is valid and in place

• DNS resolution of the controller is working

• HTTPS connection via proxy tested and successful

• SSL certificate is valid

• Ports (443) are open and reachable via proxy

• Apache/PHP-FPM restarted cleanly

[livehybrid]

Hi @LASALEM 

Are you able to check for any other logs in <php_agent_install>/logs that might be relevant? Are there any errors/warnings?

I assume you've seen this, but incase you havent its worth checking https://docs.appdynamics.com/appd/23.x/latest/en/application-monitoring/install-app-server-agents/ph... too

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