I have a main domain and 4 subdomains which are hosted in 3 VPS configured on Ubuntu 16.04, Nginx and PHP 7.3. All 5 websites are installed with latest version of WordPress.
From the time I changed my name servers to CloudFlare I keep getting 522 error. However I have tried whitelisting CloudFlare IP addresses in UFW, added Proxy time out settings in Nginx. Below is the configuration with timeout settings:
fastcgi_cache_path /var/cache/ngx_fastcgi levels=1:2 keys_zone=fastcgi_cache:10m inactive=10m max_size=64m;
fastcgi_cache_use_stale error timeout invalid_header updating http_500;
fastcgi_ignore_headers Cache-Control Expires Set-Cookie;
reset_timedout_connection on; client_body_timeout 12; client_header_timeout 12; send_timeout 10; proxy_connect_timeout 600;
client_body_buffer_size 128k; client_header_buffer_size 1k; client_max_body_size 100M; large_client_header_buffers 4 256k;
But still when CloudFlare is enabled I get 522 error. How to resolve this issue? Can someone help me with this please?