We are having trouble with a website for a free and open source project. The website and its three components are as follows. Its running on a CenOS 7 VM hosted by someone else (PaaS).site: www.cryptopp.com (apache)manual: www.cryptopp.com/docs (doxygen)wiki: www.cryptopp.com/wiki (mediawiki)The Apache version is Apache/2.4.6 (CentOS). The PHP version is 5.4.16 (cli) (built: Aug 11 2016 21:24:59). The Mediawiki version is 1.26.4.The main site is OK and can be reached through both cryptopp.com and www.cryptopp.com in all browsers and user agents. The manual is OK and can be reached through both cryptopp.com/docs and www.cryptopp.com/docs in all browsers and user agents.The wiki is OK under most Browsers and all tools. Safari is OK. Internet Explorer is OK. Chrome is untested because I don't use it. Command line tools like cURL and wget are OK. A trace using wget is below.The wiki is a problem under Firefox. It cannot be reached at either cryptopp.com/wiki and www.cryptopp.com/wiki in Firefox. Firefox displays an error on both OS X 10.8 and Windows 8. Firefox is fully patched to the platform. The failure is:We know the problem is due to a recent change to direct all traffic to HTTPS. The relevant addition to httd.conf is below. The change in our policy is due to Chrome's upcoming policy change regarding Security UX indicators.I know these are crummy questions (none of us are webmasters or admins in our day job)... What is the problem? How do I troubleshoot it? How do I fix it?wget trace$ wget http://cryptopp.com/wiki/ --2016-11-05 12:53:54--  http://cryptopp.com/wiki/Resolving cryptopp.com (cryptopp.com)... 192.210.150.121Connecting to cryptopp.com (cryptopp.com)|192.210.150.121|:80... connected.HTTP request sent, awaiting response... 302 FoundLocation: https://www.cryptopp.com/wiki/ [following]--2016-11-05 12:53:54--  https://www.cryptopp.com/wiki/Resolving www.cryptopp.com (www.cryptopp.com)... 192.210.150.121Connecting to www.cryptopp.com (www.cryptopp.com)|192.210.150.121|:443... connected.HTTP request sent, awaiting response... 301 Moved PermanentlyLocation: https://cryptopp.com/wiki/Main_Page [following]--2016-11-05 12:53:54--  https://cryptopp.com/wiki/Main_PageConnecting to cryptopp.com (cryptopp.com)|192.210.150.121|:443... connected.HTTP request sent, awaiting response... 200 OKLength: unspecified [text/html]Saving to: index.htmlindex.html              [ <=>                ]  20.04K  --.-KB/s    in 0.03s   2016-11-05 12:53:54 (767 KB/s) - index.html saved [20520]Firefox access_log# tail -16 /var/log/httpd/access_log<removed irrelevant entries>71.244.244.203 - - [05/Nov/2016:13:00:52 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:52 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:53 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:53 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:53 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:53 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:53 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:53 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:53 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:54 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.071.244.244.203 - - [05/Nov/2016:13:00:54 -0400] GET /wiki/Main_Page HTTP/1.1 302 20 https://www.cryptopp.com/ Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:48.0) Gecko/20100101 Firefox/48.0httd.conf change<VirtualHost *:80>    ServerName www.cryptopp.com    ServerAlias *.cryptopp.com *.cryptopp.* cryptopp.com    <IfModule mod_rewrite.c>        RewriteEngine On        RewriteCond %{REQUEST_METHOD} ^TRACE        RewriteRule .* - [F]        RewriteCond %{REQUEST_METHOD} ^TRACK        RewriteRule .* - [F]        #redirect all port 80 traffic to 443        RewriteCond %{SERVER_PORT} !^443$        RewriteRule ^/?(.*) https://www.cryptopp.com/$1 [L,R]    </IfModule>    </VirtualHost><VirtualHost *:443>    ServerName www.cryptopp.com    ServerAlias *.cryptopp.com *.cryptopp.* cryptopp.com</VirtualHost>
Firefox The page isnt redirecting properly for a Wiki (all other Pages and UAs are OK)
php;mod rewrite;mediawiki;firefox
Browsers (including Firefox) sometimes cache the fact that a URL redirects. If you have changed your rewrite rules, make sure you clear the cache in the browser before re-testing. (Although you wouldn't usually see evidence in your server log in that case.) As for how to investigate, I use Live HTTP Headers extension for Firefox to figure out what HTTP(S) requests are actually being made by Firefox in situations like this.I think in your case you may have had a 301 redirect configured at one point from /wiki/Main_Page to /wiki/.   Firefox got that permanent redirect into it's cache.   Then later when it got /wiki/ it found that was a 302 redirect to /wiki/Main_Page.  302 temporary redirects are not cached, so it was doing:Fetch from server /wiki/, 302 to /wiki/Main_PageFetch from cache /wiki/Main_Page, 301 to /wiki/Fetch from server /wiki/, 302 to /wiki/Main_PageFetch from cache /wiki/Main_Page, 301 to /wiki/Fetch from server /wiki/, 302 to /wiki/Main_PageFetch from cache /wiki/Main_Page, 301 to /wiki/...Error, infinite redirect