add failsites

ansible/roles/nginx_proxy/templates/proxy.conf.j2

@@ -1,6 +1,6 @@
 upstream backend {
     {% for server in upstream_servers %}
-    server {{ server }} max_fails=1 fail_timeout=1s;
+    server {{ server }} max_fails=1 fail_timeout=5s;
     {% endfor %}
 }
 
@@ -12,12 +12,20 @@ server {
     ssl_certificate /etc/nginx/ssl/{{ ssl_cert_file }};
     ssl_certificate_key /etc/nginx/ssl/{{ ssl_key_file }};
 
+    error_page 502 503 504 /custom_50x.html;
+
+    location = /custom_50x.html {
+        root /var/www/errors;
+        internal;
+    }
+
     location / {
         proxy_pass http://backend;
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
         proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_504;
+        proxy_intercept_errors on;
     }
 
     location /health {
@@ -26,4 +34,4 @@ server {
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
     }
-}
+}