Custom nginx.conf from ConfigMap in Kubernetes

Nothing complex, it's the root directory in the nginx.conf is not defined correctly.

Checking the logs with kubectl logs <<podname>> -n <<namespace>> gives why the 404 error is happening for a particular request.

xxx.xxx.xxx.xxx - - [02/Oct/2020:22:26:57 +0000] "GET / HTTP/1.1" 404 153 "-" "curl/7.58.0" 2020/10/02 22:26:57 [error] 28#28: *1 "/etc/nginx/html/index.html" is not found (2: No such file or directory), client: xxx.xxx.xxx.xxx, server: localhost, request: "GET / HTTP/1.1", host: "xxx.xxx.xxx.xxx"

It's because of location inside your configmap is referring to wrong directory as root root html.

Change the location to a directory which has index.html will fix the issue. Here is the working configmap with root /usr/share/nginx/html. However this could be manipulated as you want, but we need to make sure files exist in the directory.

apiVersion: v1kind: ConfigMapmetadata:  name: nginx-confdata:  nginx.conf: |    user nginx;    worker_processes  1;    events {      worker_connections  10240;    }    http {      server {          listen       80;          server_name  localhost;          location / {            root   /usr/share/nginx/html; #Change this line            index  index.html index.htm;        }      }    }