Mattermost, Inc.

Ssl_error_rx_record_too_long

The SSL_ERROR_RX_RECORD_TOO_LONG error message can indicate a misconfiguration with your SSL certificate. This has been reported with providers like Komodo.

To solve this, consider using Let’s Encrypt as an SSL provider.

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SSL_ERROR_RX_RECORD_TOO_LONG appears when you try to make a SSL connection and your target is simply HTTP: ssl_error_rx_record_too_long and Apache SSL [closed]

Better check your proxy configuration - using Let’s Encrypt certificate will get you into obscure troubles as they aren’t trusted by all ssl libraries. Java doesn’t trust them.