Ubuntu 20.04 (Focal Fossa) has disabled all TLS versions < TLSv1.2 by default in openssl. In case you still need TLS 1.0 (for e.x. because of legacy clients), you can enable it with the following (HAProxy 2.0.14): bind *:443 ssl crt /etc/haproxy/certs/ ssl-min-ver TLSv1.0 ciphers ALL:@SECLEVEL=1