HandshakeException: Connection Terminated During Handshake
The “HandshakeException: Connection Terminated During Handshake” error occurs when a connection is terminated unexpectedly during the handshake process. The handshake is an initial negotiation between a client and a server to establish a secure connection using SSL/TLS protocols.
There can be several reasons for this error. Let’s explore a few possible causes and their solutions:
1. Server Certificate Issues
One common cause of this error is an invalid or misconfigured server certificate. When a client tries to establish a secure connection, it verifies the server’s certificate to ensure its authenticity and integrity. If the certificate is expired, self-signed, or doesn’t match the domain, the handshake can fail.
To resolve this issue, check the server certificate for any problems. Ensure that the certificate is valid and properly configured. You may consider obtaining a valid certificate from a trusted certificate authority (CA) and installing it correctly on the server.
2. Protocol and Cipher Mismatch
Another possible cause is a mismatch between the protocols and ciphers supported by the client and server. During the handshake, the client and server negotiate the encryption protocol and cipher to be used for the secure connection. If the server doesn’t support any of the client’s preferred options, the handshake can fail.
To address this issue, ensure that the client and server support compatible protocols and ciphers. You may need to update the server’s configuration to enable the necessary protocols and ciphers or adjust the client’s settings to use supported options.
3. Network Connectivity Issues
Sometimes, network connectivity problems can cause the handshake to fail. This can be due to firewall restrictions, network interruptions, or proxy server misconfigurations that block or interfere with the handshake process.
To troubleshoot this issue, verify that there are no network restrictions or interruptions between the client and server. Check firewall settings, network configurations, and ensure that any proxy servers are properly configured to allow SSL/TLS traffic.
Example
Let’s consider an example where a client application communicates with a server over HTTPS. Upon establishing a connection, the client receives the “HandshakeException: Connection Terminated During Handshake” error.
The client could investigate the server certificate and discover that it is a self-signed certificate. In this case, the client needs to obtain a valid SSL certificate from a trusted CA and install it on the server. Once the valid certificate is in place, the handshake should complete successfully.
Additionally, the client and server could be using different SSL/TLS protocol versions or incompatible cipher suites. The client can check its supported protocols and ciphers and adjust them to match the server’s capabilities. Similarly, the server can update its configuration to support compatible options. This should result in a successful handshake without the termination error.
Finally, if the client and server are located in separate network zones with firewall restrictions, the client might need to ensure that the necessary ports and protocols (usually port 443 for HTTPS) are allowed through the firewall. By resolving any network connectivity issues, the handshake can proceed without termination.
It’s important to note that the exact solution may vary depending on the specific context and technologies involved. Therefore, it’s recommended to investigate the error further, consider the server and client configurations, and consult relevant documentation or support resources for specific troubleshooting steps.