Full-stack Nginx reverse proxying and PHP index - php

Question

I'm trying to setup a full-stack Nginx reverse proxying server (as title says, obviously), and I'm struggling a bit when it comes to code interpretation with PHP-FPM.
Here is the so called front-end part of the proxying process (which isn't used to directly serve files, but rather to redirect the client towards the back-end servers) :
server {
listen xxx.xxx.xxx.xxx:80;
server_name localhost;
# logs...
# Here begins the reverse-proxying
# Test 2nd backend server
location /test {
proxy_pass http://127.0.0.1:82/;
}
# default main site (has to be at the end since location checks file hierarchy)
location / {
proxy_pass http://127.0.0.1:81/;
}
And then, here are my two reversed server blocks.
The first one is the main site, which should be served by default by accessing domain.com :
server {
listen 127.0.0.1:81;
server_name main;
# logs...
root /var/www/main;
gzip on;
gzip_types "*";
expires 10m;
location / {
try_files $uri = 404;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/run/php-fpm.socket;
include /etc/nginx/fastcgi.conf;
}
}
And here is the second "test" one, which is should access when trying domain.com/test :
server {
listen 127.0.0.1:82;
server_name test;
root /var/www/test;
gzip on;
gzip_types "*";
expires 10m;
try_files $uri = 404;
fastcgi_split_path_info ^(.+\.php)(/.+)$;
fastcgi_pass unix:/run/php-fpm.socket;
include /etc/nginx/fastcgi.conf;
}
}
Doing so using reverse proxying would allow me to actually only use one port, and the most important, it hides which and how much virtual servers are actually running here.
So, what's the problem ?
Well, it's more about HOW are PHP and indexes managed by nginx reverse proxying than about reverse proxying itself.
When I'm using index.html files in both :81 and :82 servers, it works fine, the index directive works perfectly, and the server returns /var/www/main/index.html when accessing domain.com, and /var/www/test/index.html when accessing domain.com/test.
However, the problem happens when I'm using index.php files. In this case, only using the URLs up there leaves me with a 404 error in both cases. I need to explicitely specify index.php in the URL, eg. domain.com/test/index.php to make it work, which I don't want to have to.
I haven't found any thread or documentation dealing with such a specific case, and that's why I'm coming here to ask if anyone has more informations on indexes behavior with PHP ?
Thanks by advance for your answer(s), and I'll gladly take anything you have at this point since I've been struggling for quite a long time with this problem.

Answer 1

You need to set this to load index.php files by default:
location / {
index index.php index.html index.htm;
// ...other configurations
}