Note on Nginx and Azure

[smorris12]

This is not a bug but I didn't know how else to report this for those using Nginx with Moodle and Azure IDP. If after upgrading either Moodle or the newest version of SAML2 (thanks team, the module is great!) you get an error 500 (Bad Gateway), add the following to the site config for the nginx configuration for your Moodle site in the server section:

server {
listen 443 ssl http2;

    server_name moodle.site.com;

    fastcgi_buffers 16 16k;
    fastcgi_buffer_size 32k;
    proxy_buffer_size   128k;
    proxy_buffers   4 256k;
    proxy_busy_buffers_size   256k;     

   location ~ \.php$ {     
        ... 
         }

...
}

Taken from https://stackoverflow.com/questions/57294212/502-bad-gateway-error-upstream-sent-too-big-header-while-reading-response-head