ProxyPassReverse is used for rewriting response headers related only to redirection. As per the docs, it affects only “Location”, “Content-Location” and “URI” headers on HTTP redirect responses.
The example they give is helpful (although cluttered with other concepts). Here is a more crystalized version of the example and a protocol exchange for clarity. ProxyPass "/mirror/foo/" "http://backend.example.com/"; ProxyPassReverse "/mirror/foo/" "http://backend.example.com/"; If the backend server uses a redirect to some other location on the same backend server, the reverse-proxy rewrites the ‘redirect headers’ according to the ProxyPassReverse directive. Let’s say the backend.example.com uses the location header<https://en.wikipedia.org/wiki/HTTP_location> to redirect a request http://backend.example.com/bar to http://backend.example.com/quux. The end-to-end protocol exchange looks something like (caveat: written without validating): Client Request: GET /mirror/foo/bar HTTP/1.1 Host: example.com Reverse Proxy rewrites it to the backend (courtesy of the ProxyPass directive): GET /bar HTTP/1.1 Host: backend.example.com Backend Server responds with a redirect using the location header<https://en.wikipedia.org/wiki/HTTP_location>: HTTP/1.1 302 Found Location: http://backend.example.com/quux Reverse Proxy Intervenes (courtesy of the ProxyPassReverse directive) and rewrites the Location header to be: HTTP/1.1 302 Found Location: http://example.com/mirror/foo/quux The client then reissues the request to the Location http://example.com/mirror/foo/quux and the Reverse Proxy forwards it onto http://backend.example.com/quux. Matt. From: Ananya Dey [mailto:ananyadey...@gmail.com] Sent: Tuesday, 29 January 2019 9:13 PM To: users@httpd.apache.org Subject: [users@httpd] Use of ProxyPassReverse Hi all, I am trying to connect my Apache webserver with my backend tomcat server. I am using ProxyPass to do the same. Is there a need to put ProxyPassReverse also along with it? I am not able to understand the working functionality of the two in depth. Could someone please elaborate on the same . Thanks Ananya
