im not sure but here what I have conf for
(obviously changing librenms.example.com to your actual domain name):
<VirtualHost *:443>
SSLEngine on
SSLCertificateFile /etc/pki/tls/certs/ca.crt
SSLCertificateKeyFile /etc/pki/tls/private/ca.key
<Directory "/opt/librenms/html/">
DocumentRoot /opt/librenms/html/
AllowOverride All
AllowEncodedSlashes NoDecode
Require all granted
Options FollowSymLinks MultiViews
` </Directory>`
DocumentRoot /opt/librenms/html/
ServerName librenms.example.com
CustomLog /opt/librenms/logs/access_log combined
ErrorLog /opt/librenms/logs/error_log