Symfony .htaccess DirectoryIndex not working - .htaccess

Question

I am deploying my symfony application to production, i have placed the symfony application in the root folder
/var/www/html and have set the apache2 root directory to /var/www/html/web but the DirectoryIndex in the .htaccess file is not redirecting to the file app.php
On the url xxx.xxx.xx.xx/ i get the list of all the documents in /var/www/html/web folder, and if i do xxx.xxx.xx.xx/app.php the application loads.
I don't understand how to get the DirectoryIndex in the .htaccess to work.
I have been going through the following stack questions types but they don't work for me:
Redirect all requests to web/app.php in Symfony
Symfony: htaccess to hide app.php or app_dev.php
symfony2 rewrite rules .htaccess app.php
Another post suggested to set the apache2 root directory as /var/html instead of /var/html/web but that doesn't work either. Because the url xxxx.xxx.xx.xx/ deplays the content of the directory /var/html
The closest to a solution i came to was to rename the file app.php to index.php which got the root url xxx.xxx.xx.xx/ to load, but then all the 'sub' urls ( like xxxx.xxx.xx.xx/offer/9/Alternance_Apprentissage_graphiste_chez_Eggs) fails with a 404 Not Found error.
It is due to .htaccess file not redirecting properly the urls, because the url xxxx.xxx.xx.xx/app.php/offer/9/Alternance_Apprentissage_graphiste_chez_Eggs works fine.
My .htaccess file looks like this (it is the default generated file):
DirectoryIndex app.php
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI}::$1 ^(/.+)/(.*)::\2$
RewriteRule ^(.*) - [E=BASE:%1]
RewriteCond %{HTTP:Authorization} .
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^app\.php(/(.*)|$) %{ENV:BASE}/$2 [R=301,L]
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule .? - [L]
RewriteRule .? %{ENV:BASE}/app.php [L]
</IfModule>
<IfModule !mod_rewrite.c>
<IfModule mod_alias.c>
RedirectMatch 302 ^/$ /app.php/
</IfModule>
</IfModule>
Any help appreciated. This is critical because i cannot get my application to go on production.
UPDATE
#shevron 's is right. From his answer "It is possible that .htaccess files are not parsed at all by your Apache setup." and "Check your main Apache configuration for AllowOverride on that directory. Try to set it to AllowOverride All and restart your Apache - see if that works."
I did the following:
I set my Apache Configuration as following :
<VirtualHost *:80>
ServerAdmin webmaster#localhost
DocumentRoot /var/www/html/web
<Directory "/var/www/html/web">
AllowOverride All
Allow from All
</Directory>
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
This did not work.
#shevron did i not write that properly?
But further i put all the configurations from the .htaccess file into the Main Apache Configurations as such and this made the redirection work:
<VirtualHost *:80>
ServerAdmin webmaster#localhost
DocumentRoot /var/www/html/web
<Directory "/var/www/html/web">
AllowOverride All
Allow from All
</Directory>
DirectoryIndex app.php
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI}::$1 ^(/.+)/(.*)::\2$
RewriteRule ^(.*) - [E=BASE:%1]
RewriteCond %{HTTP:Authorization} .
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^app\.php(/(.*)|$) %{ENV:BASE}/$2 [R=301,L]
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule .? - [L]
RewriteRule .? %{ENV:BASE}/app.php [L]
</IfModule>
<IfModule !mod_rewrite.c>
<IfModule mod_alias.c>
RedirectMatch 302 ^/$ /app.php/
</IfModule>
</IfModule>
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
So now the redirection is working.

Answer 1

It is possible that .htaccess files are not parsed at all by your Apache setup (in fact, this is probably recommended for single-tenant production servers for both performance and security reasons).
Check your main Apache configuration for AllowOverride on that directory. Try to set it to AllowOverride All and restart your Apache - see if that works.
If it works, I suggest moving the contents of your .htaccess file into a <Directory> or <VirtualHost> section in the main Apache configuration file (or better yet in a separate file included by it) and setting AllowOverride None.
I found this: http://symfony-check.org/permalink/optimize-apache-avoid-htaccess which is specific for Symfony with some details, although I don't know if its up-to-date as I'm not a Symfony user.