One more note: https://github.com/netty/netty/pull/5321/files is an equivalent PR setting the session ID context to a constant value in netty (which is also a server using OpenSSL). This is in line with the documentation on SSL_CTX_set_session_id_context ( https://wiki.openssl.org/index.php/Manual:SSL_CTX_set_session_id_context(3) ):
> Sessions are generated within a certain context. When exporting/importing sessions with *i2d_SSL_SESSION*/*d2i_SSL_SESSION* it would be possible, to re-import a session generated from another context (e.g. another application), which might lead to malfunctions. Therefore each application must set its own session id context *sid_ctx* which is used to distinguish the contexts and is stored in exported sessions. The *sid_ctx* can be any kind of binary data with a given length, it is therefore possible to use e.g. the name of the application and/or the hostname and/or service name ...
