The underlying connection was closed: An unexpected error occurred on a receive
I have a 2008 IIS server with .NET1.1 framework client to another 2008 server through LTM Virtual server with SSL offloading.
Whenever the .NET client tries to talk to the Virtual I get a "The underlying connection was closed: An unexpected error occurred on a receive" back.
This works fine if I remove the client/server ssl profile and pass through but breaks when ssl client and server profiles are applied.
HTTP profile on or off does not matter. OneConnect on or off does not matter. Single pool member for testing.
I've tried using an iRule to respond immediately to the 100 continue. I've tried turning off the 100 continue from client side. Neither help, no real reason to think this is an issue but just in case.
I set up an iRule to log the request and response and it looks to me like the response is incomplete.
I believe this broke when we went from 10.2.4 to 11.5.3 ... It has been a long time, I'm just getting back to it.
Any suggestions on what else to try? I can't remove the serverssl profile and send requests back to the pool member in plaintext unfortunately. It only talks via SSL.
This was worked around by enabling the client ssl option "Don't insert empty fragments". Seems to have something to do with CBC ciphers
Apparently this option is supposed to be enabled by default but on our system it is "options none" on the default client ssl profile. I suspect it has something to do with us maintaining the same config since v7 or v8 and upgrading on top over the years to v9 v10 and then v11.
Interestingly with it breaking from v10 to v11. I still have old configs from our v10 setup and it's options none there also.... This doesn't seem to be a new option.