Redirect http into https using load balancer

https://forums.aws.amazon.com/thread.jspa?messageID=745509

The Apache block above caused our ELB health check to fail from the HTTP 301 response. To allow this and other local requests over HTTP while redirecting external requests through the ELB to HTTPS, adjust the rewrite condition to match on http instead of a negative match on https:

RewriteEngine on
RewriteCond %{HTTP:X-Forwarded-Proto} ^http$
RewriteRule .* https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]