browser reports ERR_SSL_PROTOCOL_ERROR through V11

Question

The latest browser reports "ERR_SSL_PROTOCOL_ERROR" error when connecting via HTTPS using LTM version V11. However, the connection works fine with V14. Could you please provide guidance on how to configure the SSL profile for V11 to ensure compatibility with the latest browsers?

whisperer · Answer

You need to upgrade the BIG-IP software! Ciphers change every few years, and F5 updates these by manner of updates to both TMM and OpenSSL libraries. At the end of 2023, BIG-IP v14 is EOL, so your version of code is simply ancient. Support will not help you, and anyone else in their right mind will not help you. You simply need to upgrade. Please see the following for cipher support in different versions of code:https://my.f5.com/manage/s/article/K05134218Keep in mind, you can't upgrade old hardware, so you may need to buy new hardware. Also, you may not be able to buy support anymore on your hardware, and if you cannot extend the service check date, you cannot upgrade to code newer than that date.It is also end of year. You have a business use case, perhaps leftover end of year budget left, some considerations.Good luck.

thomasliu · Answer

Thank you for your response. The current version of my LTM1600 is 11.4. Upon reviewing the official information, I have found that 11.5 is already sufficient to support the current secure encryption algorithms, such as the AES-GCM cipher suites. Therefore, I intend to upgrade to version 11.5. Do you agree with my plan?https://my.f5.com/manage/s/article/K13156#11.5.0

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