TLS handshake: no response to client hello

Hello,

Since a couple of days, we are facing an issue with TLS handshake between our active probing tool and our SBCs.

TCP connection is established properly, however our SBCs are not asnwering to Client Hello coming from the active probing tool (probe). CA certificates are installed in the SBCs since several months ago.

Checking atcpd logs from the SBCs, we can see the following:

Line 44315: Jan 21 20:43:34.872 [MINOR] (2) OpenSSL Error1408A10B:SSL routines:SSL3_GET_CLIENT_HELLO:wrong version number:s3_srvr.c:957
Line 45272: Jan 21 21:09:32.431 [MINOR] (1) OpenSSL Error1407609C:SSL routines:SSL23_GET_CLIENT_HELLO:http request:s23_srvr.c:414