How can i setup varnish for my symfony app?

Question

i want to use varnish in my symfony app for cache control,

i have used virtual host, here is my virtual host file.

<VirtualHost *:80>     
ServerAdmin webmaster@localhost     
ServerName varnish-local.com     
ServerAlias www.varnish-local.com     
DocumentRoot /var/www/html/varnish-software/public     
DirectoryIndex index.php      
<Directory /var/www/html/varnish-software/public>         
Options Indexes FollowSymLinks         
AllowOverride All         
Require all granted     
</Directory>      

ErrorLog ${APACHE_LOG_DIR}/symfony_error.log     
CustomLog ${APACHE_LOG_DIR}/symfony_access.log combined </VirtualHost>

vcl 4.1;
backend default {
    .host = "127.0.0.1";
    .port = "8000";
}

sub vcl_recv {
    if (req.method == "PURGE") {
        return (purge);
    }
}

sub vcl_backend_response {
    if (beresp.status == 404 || beresp.status == 500) {
        set beresp.ttl = 0s;
    }
}

sub vcl_deliver {
    if (obj.hits > 0) {
        set resp.http.X-Cache = "HIT";
    } else {
        set resp.http.X-Cache = "MISS";
    }
}

when i run my app from symfony:serve command, then i see that my varnish serer is running through http://127.0.0.1:6081/ but how can i use it with my 8000 port, also how can i use it with my virtual host.

when i run varnish-local.com i want to get data from varnish server, so instead of using 127.0.0.1:6081 i want to use varnish in my varnish-local.com.

so can anyone please provide information regarding this issue, thank you.

Answer 1

Running Varnish on port 8000

The built-in listening port for Varnish is indeed 6081. This is done to avoid port clashes with existing servers.

The -a runtime parameter can be used to set it to values like 80 or 8000. Here's an example varnishd command including the common runtime parameters:

varnishd \
      -a :8000 \
      -a localhost:8443,PROXY \
      -p feature=+http2 \
      -f /etc/varnish/default.vcl \
      -s malloc,256m

This command will probably be part of your systemd configuration. You can choose to run this command directly on your local machine for testing.

A better VCL file

The VCL code you're using is pretty bare bones. I suggest you use the example VCL file we created at Varnish Software: https://www.varnish-software.com/developers/tutorials/example-vcl-template/

While it's not framework-centrics, it does work pretty will out-of-the-box. I'm using it myself for a Symfony website I built.

If you're using specific cookies in your Symfony application, you might need some site-specific tuning though.

Virtual hosts & Varnish

Varnish supports virtual hosts out-of-the-box and will create a hash that identifies a cached object based on the URL and the Host header.

It's this Host header that is used by HTTP to enforce multiple domains on a single server. That's basically what Virtual hosting does.