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Nginx Config Explained: Change the Port, Root and Index on Amazon Linux 2023

By Ravindra Bagale, AWS & DevOps trainer · LinkedIn · Published: 29 September 2026 · Last updated: 30 September 2026

An Nginx website is defined by a server block: listen sets the port, root sets the folder the files come from, and index sets the file sent for /. On Amazon Linux 2023, create your own file such as /etc/nginx/conf.d/tujanena.conf with listen 90;, root /var/www/tujanena;, index shayari.html; and charset utf-8;, run sudo nginx -t, then sudo service nginx reload. For a custom port, also add an inbound rule for that port in the security group, preferably from My IP.

sudo mkdir -p /var/www/tujanena
echo '<!DOCTYPE html><html lang="mr"><head><meta charset="utf-8"><title>Shayari</title></head><body><h1>तुझ्याविना...</h1></body></html>' | sudo tee /var/www/tujanena/shayari.html
sudo tee /etc/nginx/conf.d/tujanena.conf > /dev/null <<'EOF'
server {
    listen 90;
    listen [::]:90;
    server_name _;
    root /var/www/tujanena;
    index shayari.html;
    charset utf-8;
}
EOF
sudo nginx -t && sudo service nginx reload
curl -I http://localhost:90          # expect HTTP/1.1 200 OK ... charset=utf-8

What do I need before changing the Nginx config?

• Nginx installed and running on Amazon Linux 2023 — see How to Install Nginx on Amazon Linux 2023.
• Basic editing with nano and sudo.
• Access to the instance's security group — see How to Open Port 80 and 443 in an EC2 Security Group.

How does Nginx use listen, root and index?

Where is the Nginx configuration on Amazon Linux 2023?

The default server block in nginx.conf looks like this (shortened):

server {
    listen       80;
    listen       [::]:80;
    server_name  _;
    root         /usr/share/nginx/html;
    include /etc/nginx/default.d/*.conf;
}

It has no index line, so Nginx uses its built-in default, index.html. Nginx configuration has its own simple syntax: a directive, its values, and a semicolon; blocks go inside { }.

How do I change the port, root and index in Nginx?

Step 1 — Back up, but outside conf.d

sudo cp /etc/nginx/nginx.conf ~/nginx.conf.backup

Keep backups in your home folder. A copy such as tujanena-copy.conf inside /etc/nginx/conf.d/ is loaded as a second site.

Step 2 — Create the root folder and the index page

sudo mkdir -p /var/www/tujanena
sudo nano /var/www/tujanena/shayari.html

Paste a small page with some Marathi text, save with Ctrl+O, Enter, and exit with Ctrl+X:

<!DOCTYPE html>
<html lang="mr">
<head><title>Shayari</title></head>
<body style="font-family:sans-serif;text-align:center;padding-top:60px">
  <h1>तुझ्याविना...</h1>
  <p>Served by Nginx from /var/www/tujanena on port 90.</p>
</body>
</html>

(This page has no <meta charset> on purpose, so you can see what charset utf-8; fixes in Step 5.) Files created with sudo get 644 and folders 755, which Nginx can read.

Step 3 — Write your own server block

sudo nano /etc/nginx/conf.d/tujanena.conf

server {
    listen 90;                 # the port (IPv4)
    listen [::]:90;            # the same port on IPv6 – no space inside [::]:90
    server_name _;             # any name; later your domain
    root /var/www/tujanena;    # the folder with the files
    index shayari.html;        # the page sent for "/"
}

Every line inside the block ends with ;. Using a new port keeps the default site on port 80 untouched, so nothing else breaks.

Step 4 — Test the syntax, then reload

sudo nginx -t
# nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
# nginx: configuration file /etc/nginx/nginx.conf test is successful
sudo service nginx reload
curl -I http://localhost:90

reload applies the change without dropping visitors. If nginx -t fails, fix the file first — a failed test never touches the running site.

Step 5 — Fix Marathi text with charset utf-8

Open http://<PUBLIC_IP>:90 (after Step 6) or run curl http://localhost:90. In the browser the Marathi line may show as strange symbols, because neither the page nor the server said which character set it uses. Add one line to the server block:

    charset utf-8;

Then sudo nginx -t && sudo service nginx reload. Now curl -I http://localhost:90 shows Content-Type: text/html; charset=utf-8 and the Marathi text is correct. In your real pages, also keep <meta charset="utf-8">.

Step 6 — Open the port in the security group

Nginx now listens on 90, but the security group still blocks it: the page just keeps loading and then times out. EC2 → the instance → Security → security group → Edit inbound rules → Add rule → Custom TCP, port 90, source My IP → Save rules. Security Group is the wall with fire around the server; only the gates (ports) you open let visitors in. For a quick class demo 0.0.0.0/0 works, but My IP is the safe default. Now http://<PUBLIC_IP>:90 shows your shayari page. 🎉

Step 7 — Try it: break it on purpose

Put each change back and run sudo nginx -t && sudo service nginx reload after every test.

On Ubuntu it is a little different

On Ubuntu, the site files live in /etc/nginx/sites-available/, and /etc/nginx/sites-enabled/ holds symlinks to them; edit the file in sites-available. The default web root there is /var/www/html. The directives (listen, root, index, charset) and sudo nginx -t are exactly the same.

How do I fix common Nginx config errors?

Ghabru naka 😅 — these are the usual ones: