Incorrect nginx subpath config

[tarkhil]

location /grafana/ {
    rewrite  ^/grafana/(.*)  /$1 break;
    proxy_set_header Host $http_host; 
    proxy_pass http://grafana;
  }

rewrite here will never work as expected. I guess you should try your code before publishing

/grafana/'s redirect to /login will fall outside of scope of location