MySQL SSL connections not working with phpMyAdmin and mysqli

I had a problem with phpMyAdmin not using encrypted connections.

My server was correctly configured for SSL as indicated by:

SHOW VARIABLES LIKE '%ssl%'

Which returned:

Variable_name Value
have_openssl YES
have_ssl YES
ssl_ca /etc/mysql/cacert.pem
ssl_capath
ssl_cert /etc/mysql/server-cert.pem
ssl_cipher
ssl_key /etc/mysql/server-key.pem

However when I ran:

SHOW STATUS LIKE 'Ssl_cipher'

I got back a null result, indicating that the connection was not encrypted.

Eventually I figured out that the problem was caused by using the ‘mysqli’ provider for my connections in phpMyAdmin. When I switched my connections to use ‘mysql’ instead then encryption started working and an Ssl_cipher was reported.

I’d love to know what the actual problem is, but for now I’m just happy that my connections are actually encrypted. I spent a while hacking on the mysqli dbi interface to try and get it to play nice with SSL but I didn’t make any progress.