What does the Resolver param in nginx do?

What does the Resolver param in nginx do?

nginx reverse-proxy resolver

nginx

nginx resolver -- dns

nginx dns resolver

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NGINX - Using variable in proxy_pass breaks routing

variables nginx proxypass resolver

nginx

NGINX in Openshift - NGINX can't resolve internal hostnames

nginx dns openshift openshift-origin resolver

nginx

nginx proxy_pass resolver not working

nginx reverse-proxy resolver

nginx

Are there any good articles or tips about the Nginx resolver module?

proxy nginx dns resolver

nginx