Whether NGINX belongs in front, instead, or not at all.
€55 an hour for the decision. A 502 is not consulting. That is a repair. This is the architecture question before someone rewrites the vhosts.
Replace Apache, proxy to it, or leave the panel alone
NGINX and PHP-FPM is the usual answer. Apache is kept only if .htaccess is load-bearing and nobody wants to translate it.
The panel already chose NGINX, Apache, or both. Fighting that with a hand-built proxy is how the next rebuild wins. We say which template to use.
A second cache in NGINX may be wasted. Consulting includes “do not add this”. The edge already caches the static files.
A recommendation. Implementation is optional.
Proxy or not, where the cache bypass goes, and what the panel will overwrite. You can take the note to someone else. If you want it built, that is €55/hour or a setup from €149, quoted separately.
€55. No project attached.
Minimum 1 hour. No root is required for the conversation. Access comes only if you later ask for the change.
About to put NGINX in front of a panel?
Tell us the panel and whether Cloudflare is already on. No root password in the first message.