From Boldcore's wiki
Working VirtualHost config for reverse proxy
<VirtualHost address.tld:443> ServerName address.tld ServerAlias address.tld ProxyPass / https://reverse.proxy.address/ ProxyPassReverse / https://reverse.proxy.address/ ProxyRequests Off ProxyPreserveHost On SSLProxyCheckPeerCN off SSLProxyCheckPeerName off SSLProxyCheckPeerExpire off ## For letsencrypt Include /etc/letsencrypt/options-ssl-apache.conf ## For letsencrypt SSLCertificateFile /etc/letsencrypt/live/address.tld/cert.pem SSLCertificateKeyFile /etc/letsencrypt/live/address.tld/privkey.pem SSLCertificateChainFile /etc/letsencrypt/live/address.tld/chain.pem SSLProxyEngine On </VirtualHost>