The issue stemmed from my Nginx configuration, which acts as a reverse proxy in front of the Apache server hosting SuiteCRM. Initially, I didn’t consider this because the login had worked previously and then stopped. For anyone encountering a similar setup with multiple sites using Nginx as a proxy, ensure you set the following in the SuiteCRM section:
client_max_body_size 100M;
proxy_buffer_size 256k;
proxy_buffers 4 512k;
proxy_busy_buffers_size 512k;
This should help others who face a similar issue with proxy settings affecting SuiteCRM.
Additionally, my global Nginx settings are:
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Forwarded-Port $server_port;
proxy_http_version 1.1;
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection 'upgrade';
proxy_cache_bypass $http_upgrade;
proxy_redirect off;
proxy_buffering off;
proxy_set_header Connection keep-alive;
expires 30d;