[error] Unable to initialize TLS servername extension callback (incompatible OpenSSL version?)

You can encounter the following error:

[error] Unable to initialize TLS servername extension callback (incompatible OpenSSL version?)

It could be related to OpenSSL version as the error message says

but in my case it was related to the location of the LoadModule directive for SSL.

It was solved by moving the following LoadModule directive

to the top on other LoadModule directives.

LoadModule ssl_module /usr/lib64/httpd/modules/mod_ssl.so