Facing issue in varnish configuration

[Mayur Bhuva]

I have installed the varnish on the server successfully.

Now I want to configure it with Magento 2

Please find the current values of all files below.

Server IP: 4.1.173.181

Magento 2 Admin:

Stores > Configuration > ADVANCED > System > Full Page Cache

Caching Application: Varnish Cache (Recommended)

Varnish Configuration:
    Access list: 4.1.173.181
    Backend Host: 4.1.173.181
    Backend Port: 8080

/etc/varnish/default.vcl

#
# This is an example VCL file for Varnish.
#
# It does not do anything by default, delegating control to the
# builtin VCL. The builtin VCL is called when there is no explicit
# return statement.
#
# See the VCL chapters in the Users Guide at https://www.varnish-cache.org/docs/
# and http://varnish-cache.org/trac/wiki/VCLExamples for more examples.

# Marker to tell the VCL compiler that this VCL has been adapted to the
# new 4.0 format.
vcl 4.0;

# Default backend definition. Set this to point to your content server.
backend default {
.host = "4.1.173.181";
.port = "8080";
}

sub vcl_recv {
# Happens before we check if we have this in cache already.
#
# Typically you clean up the request here, removing cookies you don't need,
# rewriting the request, etc.
}

sub vcl_backend_response {
# Happens after we have read the response headers from the backend.
#
# Here you clean the response headers, removing silly Set-Cookie headers
# and other mistakes your backend does.
}

sub vcl_deliver {
# Happens when we have all the pieces we need, and are about to send the
# response to the client.
#
# You can do accounting or modifying the final object here.
}

/etc/varnish/varnish.params

# Varnish environment configuration description. This was derived from
# the old style sysconfig/defaults settings

# Set this to 1 to make systemd reload try to switch VCL without restart.
RELOAD_VCL=1

# Main configuration file. You probably want to change it.
VARNISH_VCL_CONF=/etc/varnish/default.vcl

# Default address and port to bind to. Blank address means all IPv4
# and IPv6 interfaces, otherwise specify a host name, an IPv4 dotted
# quad, or an IPv6 address in brackets.
# VARNISH_LISTEN_ADDRESS=192.168.1.5
# VARNISH_LISTEN_PORT=6081
VARNISH_LISTEN_PORT=8080

# Admin interface listen address and port
# VARNISH_ADMIN_LISTEN_ADDRESS=127.0.0.1
# VARNISH_ADMIN_LISTEN_PORT=6082
VARNISH_ADMIN_LISTEN_ADDRESS=4.1.173.181
VARNISH_ADMIN_LISTEN_PORT=8080

# Shared secret file for admin interface
VARNISH_SECRET_FILE=/etc/varnish/secret

# Backend storage specification, see Storage Types in the varnishd(5)
# man page for details.
VARNISH_STORAGE="malloc,256M"

# User and group for the varnishd worker processes
VARNISH_USER=varnish
VARNISH_GROUP=varnish

# Other options, see the man page varnishd(1)
#DAEMON_OPTS="-p thread_pool_min=5 -p thread_pool_max=500 -p thread_pool_timeout=300"

/magento2/app/etc/env.php

'http_cache_hosts' => 
array (
0 => 
array (
'host' => '4.1.173.181',
'port' => '8080',
),
),

But when I run the following command to check if varnish is enabled or not, it doesn't show X-varnish in the response header. It seems that varnish is not configured with Magento 2 properly.

curl -I -v --location-trusted 'http://4.1.173.181/magento2'

Am I doing anything wrong?

Please help.