deployed a new BYOC cluster in eu-central-1 last night. nodes are healthy in AWS, but the Genesys console keeps flagging them as unreachable. getting 504s on the health check endpoint from the control plane side. network policies are open, security groups look fine. tried bouncing the nodes, no luck. feels like a DNS resolution issue on the edge side but the logs are sparse. anyone else seeing this with the latest edge agent version?
504 Gateway Timeout on the health check usually means the request hit the load balancer, but the backend service didn’t respond in time. Since you’re seeing this on the Genesys control plane side while AWS says the nodes are healthy, the issue is almost certainly TLS certificate validation or a mismatch in the expected hostname for the health endpoint. The edge agent tries to call back to Genesys for status, and if the cert chain is broken or the SNI doesn’t match the registered edge domain, the handshake hangs until the LB kills it.
Check the edge agent logs for SSL_ERROR_BAD_CERTIFICATE or similar handshake failures. If the logs are sparse, enable debug logging for the com.mendix.cloud package. You can verify the certificate chain manually from the node using openssl.
openssl s_client -connect your-edge-hostname.euc1.genesys.cloud:443 -servername your-edge-hostname.euc1.genesys.cloud
Look for the Verify return code. If it’s not 0, your node can’t trust the Genesys cert or vice versa. This often happens if you’re using a custom CA that isn’t in the node’s trust store. Add the intermediate certs to the Java truststore on the edge node.
keytool -import -alias genesys-intermediate -keystore $JAVA_HOME/jre/lib/security/cacerts -file intermediate.crt
Also, double-check that the genesys.edge.hostname property in the edge agent config matches the exact CNAME you registered in the Genesys admin console. A single character mismatch here causes the SNI validation to fail silently in some agent versions. Restart the edge service after updating the truststore. If the 504s persist, check the AWS Security Group egress rules. Sometimes outbound 443 traffic gets blocked by a newly applied NACL.
The 504 is likely a handshake timeout, not just DNS. The edge agent needs to verify the cert chain against the Genesys trust store. If your internal CA isn’t whitelisted, the connection hangs until the LB times out.
Here’s how to test the endpoint directly from the node:
curl -v -k https://api.mypurecloud.com/api/v2/platform/user/me \
-H "Authorization: Bearer <your_token>" \
-H "Host: api.mypurecloud.com"
Check the TLS handshake details in the verbose output. You’ll see where it stalls. Also, verify the edge.conf has the correct trusted_certs path. In my hybrid setup, I had to explicitly add the intermediate CA to the Java truststore on the edge server.
keytool -import -alias genesys-intermediate -file intermediate.crt -keystore $JAVA_HOME/jre/lib/security/cacerts
Don’t forget to restart the edge service after updating the keystore. It’s easy to miss that step.
Wait, are we sure this is a BYOC issue? The title says BYOC, but the symptoms sound exactly like the Direct Routing health checks we deal with in Teams. If you’re seeing 504s on the edge node health endpoint, it’s often the SBC or the load balancer dropping the TCP handshake before the TLS negotiation completes.
In our setup, we had to adjust the idle timeout on the Azure Load Balancer. The default is too aggressive for the Genesys edge agent’s heartbeat interval. We bumped it to 300 seconds. Also, check if your SBC is terminating TLS too early. The edge agent expects to talk directly to the Genesys control plane. If an intermediate proxy is stripping headers or modifying the SNI, the health check fails silently with a timeout.
Try pinging the health endpoint from the node using curl -v like mentioned above, but add --connect-timeout 5 to isolate where it hangs. If it hangs on connect, it’s network. If it hangs on SSL, it’s certs. We’ve seen this twice now with Teams integrations. Usually a config tweak on the LB fixes it.
The 504 was indeed the idle timeout on the ALB. Bumping it to 300s fixed the health checks.