Troubleshooting⚓ The following steps may help in troubleshooting the Sqreen for PHP. Check if the Sqreen extension was loaded by PHP⚓ By taking a look at the phpinfo() page, the Sqreen extension section should be present. If it isn't, then probably PHP was not correctly instructed to load the Sqreen PHP extension. Take a look at the manual installation of the php extension section in this documentation. The following can be retrieved in this table: the extension version; the daemon version; the connection status between the extension and the daemon (on the Connected line in the first section). Ensure the agent is running⚓ A sqreen-agent process should be running: $ ps aux | grep sqreen sqreen 19456 0,0 0,0 2522856 6656 s013 S+ Ven10 0:55.18 sqreen-agent If it isn't, please ensure the sqreen-agent was installed and configured to start automatically. Check for PHP logs⚓ The PHP errors (in the FPM logs or in the Apache logs) may have Sqreen related messages. Check the agent logs⚓ The sqreen-agent logs should inform you that the agent was successfully started: $ cat /var/log/sqreen/sqreen.log [INFO][2017-09-04 09:42:29,013 #15348.MainThread] sqreen-agent:91 Starting up on TCP socket 0.0.0.0:7773 [INFO][2017-08-31 09:42:29,013 #15348.MainThread] sqreen-agent:104 Sqreen-agent successfully started Check the agent debug logs⚓ The agent can be asked to report debug logs as well: $ sqreen-agent --log_level=DEBUG [INFO][2017-09-04 09:42:29,013 #15348.MainThread] sqreen-agent:91 Starting up on TCP socket 0.0.0.0:7773 [INFO][2017-08-31 09:42:29,013 #15348.MainThread] sqreen-agent:104 Sqreen-agent successfully started Ensure the extension can join the agent⚓ Since the PHP extension need to contact the agent, run the following command (from the PHP host if different from the daemon host): $ curl 127.0.0.1:7773 If you are using a different host for the daemon and your PHP host, replace 127.0.0.1 with the address of the host running the daemon. The command will either: timeout (the connection was successfully performed) terminate with a Connection refused error. In the case of a timeout, everything is fine: the agent is listening. In case of a Connection refused error, it seems this host cannot join the agent. Check your network configuration. Get more logs⚓ The Sqreen extension may be configured in debug mode. In the Sqreen .ini file, add the following directive: sqreen.log_level = 'debug' Restart Apache or FPM and query your server. The extension should create log files in the /tmp/ directory. Feel free to share these logs with us for further investigation.