Chapter 71: DevOps Projects Part 1: Linux Server, Scripts, Nginx, HTTPS and Firewall

71.6 Project 6: Nginx web server with virtual hosts

By Ravindra Bagale Last updated: 28 October 2026

Friends, one Nginx can host many sites. Today we install Nginx, add two server blocks, open port 80, and prove each hostname returns its own page.

What you will build in this project

Nginx installed and running.
Two virtual hosts with root folders.
Enabled sites and reloaded.
curl tests for each Host header.

1. Start from a real company story

At Freshworks in Chennai, marketing wanted docs.example.com and status.example.com on one small VM to save ₹4,000 a month.

One default site was breaking both brands. Leads looked wrong.

Sana added two server blocks, two root folders, and curl tests with Host headers.

Today we do the same with practice hostnames.

Picture 1: one Nginx, two sites

Ravindra Bagale's Tip

Many students edit nginx.conf for every site. Prefer sites-available and sites-enabled. Keep that habit.

2. Start and prepare

Step 1: Install Nginx

Why: Package must be present. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: apt install nginx. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 1: Install

Type this:

sudo apt-get install -y nginx 2>&1 | tail -2

You will see:

Setting up nginx ...
0 upgraded, 1 newly installed

What it means: Installed.

Example 2: Version

Type this:

nginx -v 2>&1

You will see:

nginx version: nginx/1.24.0

What it means: Version note.

Example 3: Binary

Type this:

command -v nginx

You will see:

/usr/sbin/nginx

What it means: Found.

Step 2: Check status

Why: Service must be active. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: systemctl status. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 4: Status

Type this:

sudo systemctl enable --now nginx && systemctl is-active nginx

You will see:

active

What it means: Running.

Example 5: Port

Type this:

ss -ltn | grep ':80 ' || echo 'listen check later'

You will see:

LISTEN 0 511 0.0.0.0:80

What it means: Port 80 open.

Example 6: Default curl

Type this:

curl -s -o /dev/null -w '%{http_code}' http://127.0.0.1/

You will see:

What it means: Default page lives.

Step 3: Create web roots

Why: Each site needs a folder. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: mkdir -p. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 7: Roots

Type this:

sudo mkdir -p /var/www/docs /var/www/status && sudo chown -R $USER:$USER /var/www/docs /var/www/status && ls -d /var/www/docs /var/www/status

You will see:

/var/www/docs
/var/www/status

What it means: Ready.

Example 8: Modes

Type this:

stat -c '%a %n' /var/www/docs /var/www/status

You will see:

755 /var/www/docs
755 /var/www/status

What it means: OK.

Example 9: Empty

Type this:

ls /var/www/docs | wc -l

You will see:

What it means: Fresh.

3. Build the main pieces

Step 4: Write index pages

Why: Unique body text helps. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: printf index.html. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 10: docs index

Type this:

printf '%s\n' '<!doctype html><title>docs</title><h1>docs site</h1>' > /var/www/docs/index.html && cat /var/www/docs/index.html

You will see:

<!doctype html><title>docs</title><h1>docs site</h1>

What it means: Unique body.

Example 11: status index

Type this:

printf '%s\n' '<!doctype html><title>status</title><h1>status site</h1>' > /var/www/status/index.html && cat /var/www/status/index.html

You will see:

<!doctype html><title>status</title><h1>status site</h1>

What it means: Unique body.

Example 12: wc

Type this:

wc -c /var/www/docs/index.html /var/www/status/index.html

You will see:

58 /var/www/docs/index.html
62 /var/www/status/index.html

What it means: Small pages.

Step 5: Write docs vhost

Why: server_name selects the site. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: server block file. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 13: docs conf

Type this:

printf '%s\n' 'server {' '  listen 80;' '  server_name docs.example.com;' '  root /var/www/docs;' '  index index.html;' '}' | sudo tee /etc/nginx/sites-available/docs >/dev/null && cat /etc/nginx/sites-available/docs

You will see:

server {
  listen 80;
  server_name docs.example.com;
  root /var/www/docs;
  index index.html;
}

What it means: Block ready.

Example 14: syntax peek

Type this:

grep server_name /etc/nginx/sites-available/docs

You will see:

server_name docs.example.com;

What it means: Name set.

Example 15: Mode

Type this:

stat -c '%a' /etc/nginx/sites-available/docs

You will see:

What it means: OK.

Step 6: Write status vhost

Why: Second brand, second block. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: server block file. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 16: status conf

Type this:

printf '%s\n' 'server {' '  listen 80;' '  server_name status.example.com;' '  root /var/www/status;' '  index index.html;' '}' | sudo tee /etc/nginx/sites-available/status >/dev/null && cat /etc/nginx/sites-available/status

You will see:

server {
  listen 80;
  server_name status.example.com;
  root /var/www/status;
  index index.html;
}

What it means: Second block.

Example 17: Both files

Type this:

ls /etc/nginx/sites-available/

You will see:

default
docs
status

What it means: Three files.

Example 18: grep names

Type this:

grep server_name /etc/nginx/sites-available/docs /etc/nginx/sites-available/status

You will see:

/etc/nginx/sites-available/docs:  server_name docs.example.com;
/etc/nginx/sites-available/status:  server_name status.example.com;

What it means: Distinct.

4. Automate and verify

Step 7: Enable sites

Why: Symlinks enable. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: ln -s. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 19: Enable

Type this:

sudo ln -sf /etc/nginx/sites-available/docs /etc/nginx/sites-enabled/docs && sudo ln -sf /etc/nginx/sites-available/status /etc/nginx/sites-enabled/status && ls /etc/nginx/sites-enabled/

You will see:

default
docs
status

What it means: Symlinks.

Example 20: ls -l docs

Type this:

ls -l /etc/nginx/sites-enabled/docs

You will see:

lrwxrwxrwx 1 root root 34 Oct 28 12:00 /etc/nginx/sites-enabled/docs -> /etc/nginx/sites-available/docs

What it means: Points to available.

Example 21: count enabled

Type this:

ls /etc/nginx/sites-enabled/ | wc -l

You will see:

What it means: Including default for now.

Step 8: Test config and reload

Why: nginx -t then reload. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: nginx -t && reload. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 22: Test

Type this:

sudo nginx -t

You will see:

nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful

What it means: Good.

Example 23: Reload

Type this:

sudo systemctl reload nginx && echo reloaded

You will see:

reloaded

What it means: Applied.

Example 24: Active

Type this:

systemctl is-active nginx

You will see:

active

What it means: Still up.

Step 9: curl Host tests

Why: Host header proves routing. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: curl -H. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 25: curl docs

Type this:

curl -s -H 'Host: docs.example.com' http://127.0.0.1/

You will see:

<!doctype html><title>docs</title><h1>docs site</h1>

What it means: docs body.

Example 26: curl status

Type this:

curl -s -H 'Host: status.example.com' http://127.0.0.1/

You will see:

<!doctype html><title>status</title><h1>status site</h1>

What it means: status body.

Example 27: codes

Type this:

curl -s -o /dev/null -w '%{http_code}' -H 'Host: docs.example.com' http://127.0.0.1/; echo; curl -s -o /dev/null -w '%{http_code}' -H 'Host: status.example.com' http://127.0.0.1/

You will see:

200
200

What it means: Both OK.

5. Harden and accept

Step 10: Disable default

Why: Default can confuse. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: unlink default. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 28: Disable default

Type this:

sudo unlink /etc/nginx/sites-enabled/default 2>/dev/null; sudo nginx -t && sudo systemctl reload nginx && ls /etc/nginx/sites-enabled/

You will see:

docs
status

What it means: Default gone.

Example 29: enabled only two

Type this:

ls /etc/nginx/sites-enabled/ | wc -l

You will see:

What it means: Clean.

Example 30: reload again

Type this:

sudo systemctl reload nginx && echo ok

You will see:

ok

What it means: Stable.

Step 11: Open firewall 80

Why: OS firewall must allow. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: ufw or firewalld. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 31: ufw allow

Type this:

sudo ufw allow 80/tcp 2>/dev/null || echo 'open SG instead'

You will see:

Rule added

What it means: Lab firewall.

Example 32: ss again

Type this:

ss -ltn | grep ':80 '

You will see:

LISTEN 0 511 0.0.0.0:80

What it means: Listening.

Example 33: curl external note

Type this:

echo 'from laptop: curl -H Host:docs.example.com http://SERVER_IP/'

You will see:

from laptop: curl -H Host:docs.example.com http://SERVER_IP/

What it means: Real test.

Step 12: Acceptance checklist

Why: Sana signs off when these pass. We do this before the next step so mistakes stay small and easy to undo. Read the output carefully; the numbers and names tell you if the machine is healthy.

What: All green. Follow the numbered examples below. Type each command, read the exact output, and match the meaning line before you move on. That is how real teams learn a tool.

Example 34: nginx -t

Type this:

sudo nginx -t >/dev/null && echo conf_ok

You will see:

conf_ok

What it means: Valid.

Example 35: two bodies differ

Type this:

curl -s -H 'Host: docs.example.com' http://127.0.0.1/ | grep -o docs; curl -s -H 'Host: status.example.com' http://127.0.0.1/ | grep -o status

You will see:

docs
status

What it means: Routed.

Example 36: Sign-off

Type this:

echo 'Sana: PASS'

You will see:

Sana: PASS

What it means: Done.

Check yourself

Q1. Config test command?

nginx -t

Q2. Where do site files live?

sites-available

Q3. How do we enable a site?

Symlink into sites-enabled

Q4. Port for HTTP?

Q5. Who set this up at Freshworks?

Sana

Q6. Tool to test Host header?

curl -H Host

Friends, you hosted two sites on one Nginx with virtual hosts. Did you understand? Let us try it once more. Add a third practice host and prove it with curl.

Lab: try at home

Install Nginx.
Create two roots and index files.
Write two server blocks.
Enable and reload.
curl with Host headers.

Recap

One Nginx, many server_name values.
sites-available holds configs.
sites-enabled has symlinks.
nginx -t before reload.
curl -H Host tests.