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AppDynamics Team

What are the steps to troubleshoot a Port 443 error?

Troubleshoot the error step-by-step as follows:


Step 1. Check to see whether Port 443 is opened

Check (telnet <controller-host> 443) from the agent host to make sure the port has been opened. If it's closed, open it.


Step 2. Check the proxy

If port 443 is open, but the agent still can’t telnet, check the proxy.


Does it exist? If so, curl with proxy args to see whether the network firewall/proxy is working. You want to determine whether the error is caused by the agent or whether it’s a proxy end error.

curl -x http://proxyHost:proxyPort/ -I https://<controller-host>:443/controller/rest/serverstatus


Step 3. SSL for the Java Agent

If either telnet or curl work on the port without errors, but the agent still fails with an “SSL certs missing” error, review the Enable SSL for the Java Agent documentation.


There are many SSL exception variants, of which many require expert-level debugging. If your error isn’t addressed in the above documentation, please initiate a ticket with AppDynamics customer support.


Step 4. JKK and SSL supported protocol or cipher limitations

JDK and SSL supported protocol/cipher limitations also require expert-level SSL debugging, so we recommend reaching out to AppDynamics support.

Version history
Last update:
‎02-19-2020 10:05 AM
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