website not accessible after idling some time running nginx and kubernetes - nginx

Question

My website is not accessible from the browser for a few minutes after idling or not accessing it like 30 minutes or more. I would have to reload the page for how many times to view the page and I am not sure which to debug.
the stack I am running is a Golang app behind nginx that runs on kubernetes ingress. here is part of my nginx.conf.
daemon off;
worker_processes 2;
pid /run/nginx.pid;
worker_rlimit_nofile 523264;
events {
multi_accept on;
worker_connections 16384;
use epoll;
}
http {
real_ip_header X-Forwarded-For;
set_real_ip_from 0.0.0.0/0;
real_ip_recursive on;
geoip_country /etc/nginx/GeoIP.dat;
geoip_city /etc/nginx/GeoLiteCity.dat;
geoip_proxy_recursive on;
# lua section to return proper error codes when custom pages are used
lua_package_path '.?.lua;./etc/nginx/lua/?.lua;/etc/nginx/lua/vendor/lua-resty-http/lib/?.lua;';
init_by_lua_block {
require("error_page")
}
sendfile on;
aio threads;
tcp_nopush on;
tcp_nodelay on;
log_subrequest on;
reset_timedout_connection on;
keepalive_timeout 75s;
client_header_buffer_size 1k;
large_client_header_buffers 4 8k;
types_hash_max_size 2048;
server_names_hash_max_size 512;
server_names_hash_bucket_size 64;
map_hash_bucket_size 64;
include /etc/nginx/mime.types;
default_type text/html;
gzip on;
gzip_comp_level 5;
gzip_http_version 1.1;
gzip_min_length 256;
gzip_types application/atom+xml application/javascript application/x-javascript application/json application/rss+xml application/vnd.ms-fontobject application/x-font-ttf application/x-web-app-manifest+json application/xhtml+xml application/xml font/opentype image/svg+xml image/x-icon text/css text/plain text/x-component;
gzip_proxied any;
server_tokens on;
log_format upstreaminfo '$remote_addr - '
'[$proxy_add_x_forwarded_for] - $remote_user [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent" '
'$request_length $request_time [$proxy_upstream_name] $upstream_addr $upstream_response_length $upstream_response_time $upstream_status';
map $request_uri $loggable {
default 1;
}
access_log /var/log/nginx/access.log upstreaminfo if=$loggable;
error_log /var/log/nginx/error.log notice;
resolver 10.131.240.10 valid=30s;
# Retain the default nginx handling of requests without a "Connection" header
map $http_upgrade $connection_upgrade {
default upgrade;
'' close;
}
# trust http_x_forwarded_proto headers correctly indicate ssl offloading
map $http_x_forwarded_proto $pass_access_scheme {
default $http_x_forwarded_proto;
'' $scheme;
}
map $http_x_forwarded_port $pass_server_port {
default $http_x_forwarded_port;
'' $server_port;
}
# map port 442 to 443 for header X-Forwarded-Port
map $pass_server_port $pass_port {
442 443;
default $pass_server_port;
}
# Map a response error watching the header Content-Type
map $http_accept $httpAccept {
default html;
application/json json;
application/xml xml;
text/plain text;
}
map $httpAccept $httpReturnType {
default text/html;
json application/json;
xml application/xml;
text text/plain;
}
server_name_in_redirect off;
port_in_redirect off;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
# turn on session caching to drastically improve performance
ssl_session_cache builtin:1000 shared:SSL:10m;
ssl_session_timeout 10m;
# allow configuring ssl session tickets
ssl_session_tickets on;
# slightly reduce the time-to-first-byte
ssl_buffer_size 4k;
# allow configuring custom ssl ciphers
ssl_ciphers 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:AES:CAMELLIA:DES-CBC3-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!MD5:!PSK:!aECDH:!EDH-DSS-DES-CBC3-SHA:!EDH-RSA-DES-CBC3-SHA:!KRB5-DES-CBC3-SHA';
ssl_prefer_server_ciphers on;
# In case of errors try the next upstream server before returning an error
proxy_next_upstream error timeout invalid_header http_502 http_503 http_504;
upstream default-ui-80 {
sticky hash=sha1 name=route httponly;
server 10.128.2.104:4000 max_fails=0 fail_timeout=0;
server 10.128.4.37:4000 max_fails=0 fail_timeout=0;
}
server {
server_name app.com;
listen [::]:80;
listen 442 ssl http2;
# PEM sha: a51bd3f56b3ec447945f1f92f0ad140bb8134d11
ssl_certificate /ingress-controller/ssl/default-linker-secret.pem;
ssl_certificate_key /ingress-controller/ssl/default-linker-secret.pem;
more_set_headers "Strict-Transport-Security: max-age=15724800; includeSubDomains; preload";
location / {
set $proxy_upstream_name "default-ui-80";
port_in_redirect off;
# enforce ssl on server side
if ($scheme = http) {
return 301 https://$host$request_uri;
}
client_max_body_size "1024m";
proxy_set_header Host $host;
# Pass Real IP
proxy_set_header X-Real-IP $remote_addr;
# Allow websocket connections
proxy_set_header Upgrade $http_upgrade;
proxy_set_header Connection $connection_upgrade;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Host $host;
proxy_set_header X-Forwarded-Port $pass_port;
proxy_set_header X-Forwarded-Proto $pass_access_scheme;
# mitigate HTTPoxy Vulnerability
# https://www.nginx.com/blog/mitigating-the-httpoxy-vulnerability-with-nginx/
proxy_set_header Proxy "";
# Custom headers
proxy_connect_timeout 5s;
proxy_send_timeout 3600s;
proxy_read_timeout 3600s;
proxy_redirect off;
proxy_buffering off;
proxy_buffer_size "4k";
proxy_http_version 1.1;
proxy_pass http://default-ui-80;
}
}
}
ingress controller
apiVersion: v1
kind: ReplicationController
metadata:
name: nginx-ingress-controller
labels:
k8s-app: nginx-ingress-lb
spec:
replicas: 1
selector:
k8s-app: nginx-ingress-lb
template:
metadata:
labels:
k8s-app: nginx-ingress-lb
name: nginx-ingress-lb
spec:
terminationGracePeriodSeconds: 60
containers:
- image: gcr.io/google_containers/nginx-ingress-controller:0.9.0-beta.2
name: nginx-ingress-lb
imagePullPolicy: Always
readinessProbe:
httpGet:
path: /healthz
port: 10254
scheme: HTTP
livenessProbe:
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
timeoutSeconds: 1
# use downward API
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
ports:
- containerPort: 80
hostPort: 80
- containerPort: 443
hostPort: 443
args:
- /nginx-ingress-controller
- --default-backend-service=$(POD_NAMESPACE)/default-http-backend
- --configmap=$(POD_NAMESPACE)/nginx-ingress-sticky-session
- --configmap=$(POD_NAMESPACE)/nginx-settings-configmap
- --tcp-services-configmap=$(POD_NAMESPACE)/tcp-configmaps
- --v=2
ingress
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: foo-prod
annotations:
kubernetes.io/tls-acme: "true"
kubernetes.io/ingress.class: "nginx"
ingress.kubernetes.io/affinity: "cookie"
ingress.kubernetes.io/session-cookie-name: "route"
ingress.kubernetes.io/session-cookie-hash: "sha1"
nginx.org/client-max-body-size: "1024m"
spec:
tls:
- hosts:
- foo.io
secretName: foo-secret
rules:
- host: foo.io
http:
paths:
- backend:
serviceName: foo.io
servicePort: 80
service
apiVersion: v1
kind: Service
metadata:
name: foo-prod-nginx
spec:
type: LoadBalancer
ports:
- port: 80
name: http
- port: 443
name: https
selector:
app: nginx-ingress-controller

Answer 1

The service.type=LoadBalancer allocates a public IP per k8s service, which is not how ingress works. You should expose your service as nodeport, and let ingress route traffic to it. example here
Also, if you are going to use nginx as ingress controller, you should use endpoint instead of service. Here is why