How to configure nginx as load balancer for CJP

Issue

How to configure nginx as load balancer for CJP
Is possible to use nginx as load balancer for CJP HA?

Environment

Resolution

The recommended configuration uses HAProxy and is described here in HA Configuration, we do not have a recommended configuration for nginx because only the commercial version of nginx allow checking an URL as a health check beat, see this link for more info http-health-check so if you have the commercial version of nginx you can use this configuration file

upstream backend  {
        ip_hash;
        server cje1.example.com:8181;
        server cje2.example.com:8282;
}

match server_primary {
        status 200-399;
        body !~ "primary";
}


server {
  listen 80;

  access_log /var/log/nginx/access.log;

  location / {
    proxy_pass https://backend;
    health_check uri=/ha/health-check match=server_primary interval=30s fails=3 passes=2;
    proxy_set_header Host $host;
    proxy_redirect off;

    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;

    client_max_body_size 250m;
    client_body_buffer_size 128k;

    proxy_connect_timeout 90;
    proxy_send_timeout 300;
    proxy_read_timeout 300;

    proxy_buffering off;

    proxy_temp_file_write_size 64k;
  }
}

if not you have to use something like this could work but the primary should be always the same if both servers are up

upstream backend  {
        ip_hash;
        server cje1.example.com:8181 max_fails=3 fail_timeout=30s weight=100;
        server cje2.example.com:8282 max_fails=3 fail_timeout=30s backup;
}

server {
  listen 80;

  access_log /var/log/nginx/access.log;

  location / {
    proxy_pass https://backend;
    proxy_set_header Host $host;
    proxy_redirect off;

    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;

    client_max_body_size 250m;
    client_body_buffer_size 128k;

    proxy_connect_timeout 90;
    proxy_send_timeout 300;
    proxy_read_timeout 300;

    proxy_buffering off;

    proxy_temp_file_write_size 64k;
  }
}

or if your version of nginx does not support backup directive this one trick the round robin to redirect always to the primary if it is available

upstream backend  {
        ip_hash;
        server cje1.example.com:8181 max_fails=3 fail_timeout=30s weight=100;
        server cje2.example.com:8282 max_fails=3 fail_timeout=30s;
}

server {
  listen 80;

  access_log /var/log/nginx/access.log;

  location / {
    proxy_pass https://backend;
    proxy_set_header Host $host;
    proxy_redirect off;

    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;

    client_max_body_size 250m;
    client_body_buffer_size 128k;

    proxy_connect_timeout 90;
    proxy_send_timeout 300;
    proxy_read_timeout 300;

    proxy_buffering off;

    proxy_temp_file_write_size 64k;
  }
}

Tested product/plugin versions

Nginx 1.13.8