Use Varnish cache tool with Node.js and Nginx

Question

I have two Node.js server on two different ports(3636, 4646), I used Nginx web server as a reverse proxy for my servers , my problem is how to add Varnish cache tool to both servers?

/etc/nginx/sites-enabled/yourdomain:

upstream app_yourdomain {
    server 127.0.0.1:3636;
    keepalive 8;
}

server {
    listen 0.0.0.0:8080;
    server_name yourdomain.com yourdomain;
    access_log /var/log/nginx/yourdomain.log;
    # pass the request to the node.js server with the correct headers
    # and much more can be added, see nginx config options
    location / {
      proxy_set_header X-Real-IP $remote_addr;
      proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
      proxy_set_header Host $http_host;
      proxy_set_header X-NginX-Proxy true;

      proxy_pass http://app_yourdomain/;
      proxy_redirect off;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection "upgrade";
    }
 }

/etc/nginx/sites-enabled/domain2:

server {
    listen 8080;
    server_name domain2.com;
    access_log /var/log/nginx/domain2.access.log;
    location / {
        proxy_pass    http://127.0.0.1:4646/;
    }
}

varnish config file:

DAEMON_OPTS="-a :80 \
             -T localhost:6082 \
             -f /etc/varnish/default.vcl \
             -S /etc/varnish/secret \
             -s malloc,256m"

but when I use curl -I http://localhost there is no sign of varnish :

HTTP/1.1 200 OK
Server: nginx/1.10.3 (Ubuntu)
Date: Mon, 20 Nov 2017 12:22:17 GMT
Content-Type: text/html
Content-Length: 612
Last-Modified: Mon, 18 Sep 2017 06:18:46 GMT
Connection: keep-alive
ETag: "59bf6546-264"
Accept-Ranges: bytes

/etc/varnish/default.vcl:

backend default {
    .host = "127.0.0.1";
    .port = "8080";
}

Is there anything am I missing?

Answer 1

That's hard to tell without seeing your default.vcl. Maybe you have something like this:

sub vcl_deliver {
    unset resp.http.Via;
    unset resp.http.X-Varnish;
}    

Also make sure to have the correct backend config:

backend default {
    .host = "localhost";
    .port = "8080";
}