Guide to Opening/Closing Ports on VPS (Linux& Windows)

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Published date:17/4/2026 Update:11/8/2026 Views:153 Reviews: 5.0/5283reviews

While using a VPS, opening and closing ports is a necessary task for services to function and be accessed from the outside. However, if misconfigured, you might encounter...

Guide

While using a VPS, you may need toopen portso that websites, SSH, Remote Desktop, databases, APIs, or other applications can receive incoming connections.

Conversely, ports that are no longer in use should becloseto limit unnecessary connections and increase security for the VPS.

In this article, VPTS will provide detailed instructions on how toopen, close, and check ports on Linux and Windows VPS, applicable to popular operating systems such as Ubuntu, Debian, AlmaLinux, Rocky Linux, CentOS, and Windows Server.

1. What Is a Port on a VPS?

A port can simply be understood as a network communication endpoint used by services on a VPS to receive or send connections.

A single IP address can use multiple different ports. Each application typically listens on one or several specific ports.

2. Common Ports You Need to Know

Services	Port
SSH (Linux)	22
HTTP (Website)	80
HTTPS	443
FTP	21
Remote Desktop – RDP	3389
MySQL/MariaDB	3306
PostgreSQL	5432

3. Guide to opening/closing ports on Linux VPS

3.1. For Ubuntu (UFW)

Step 1: Check UFW status

sudo ufw status

Returned result -> active->UFW is active.
Open a single port (Allow): for example, open port 80
The result will return as shown in the image below

Step 2: Open a port

Example: need to open port80:

sudo ufw allow 80/tcp

If successful, UFW will add a rule allowing TCP connections to port 80.
You just need to replace80with the required port.

Step 3: Open HTTPS port 443

sudo ufw allow 80,443/tcp

Delete opened rule

sudo ufw delete allow 80

The result will return as shown in the image below

Step 5: Check ports currently allowed by UFW

Run:

sudo ufw status numbered

The result will return as shown in the image below

If you want to delete by index number, run a command similar to the following

sudo ufw delete 5

No. are series of numbers 1, 2, 3, 4, 5, 6 as you see

3.2. For FirewallD (CentOS 7+, RHEL, AlmaLinux)

Operating systems in the RHEL family typically usefirewalldto manage the firewall.

Step 1: Check FirewallD

Run:

sudo systemctl status firewalld

Step 2: Start FirewallD if it is not running

Run:

systemctl start firewalld
systemctl enable firewalld

Then verify:

sudo systemctl status firewalld

Returned result active (running) ->ok

Step 3: Open a port

Example: opening TCP port8080:

sudo firewall-cmd --add-port=8080/tcp --permanent
sudo firewall-cmd --reload

If the result shows success, it is successful

Step 4: Open ports 80 and 443

Run:

firewall-cmd --permanent --add-port=80/tcp
firewall-cmd --permanent --add-port=443/tcp
firewall-cmd --reload

All succeeded, linewarning: ALREADY_ENABLED: 80:tcp is not an error; it means that port 80 was already open beforehand.

Step 5: Check list of opened ports

Run:

sudo firewall-cmd --list-ports

Displays all opened ports

3.3. Open port with IPTables

Some legacy VPSs or Linux systems still manage firewalls directly using IPTables.

Example: opening TCP port8080:

sudo iptables -A INPUT -p tcp --dport 80 -j ACCEPT

Check open ports

iptables -L -n

Displays all ports as shown in the image

4. Guide to opening/closing ports on Windows VPS

4.1. Open port using Windows Firewall (popular method)

Step 1: Open firewall

Click search and typeWindows Defender Firewall with Advanced Security. Select Inbound Rules -> New Rule.

Step 2: Select rule type

Select port and click Next

Select TCP or UDP, enter the port to open

Step 3: Allow connection

Select Allow the connection and click Next -> Next

Name and finish

Related articles to refer to below

4.2. Open port using CMD

Open port 80

netsh advfirewall firewall add rule name="Open Port 80" dir=in action=allow protocol=TCP localport=80

Open port 443

netsh advfirewall firewall add rule name="Open Port 443" dir=in action=allow protocol=TCP localport=443

Open Remote Desktop port (3389)

netsh advfirewall firewall add rule name="RDP Port 3389" dir=in action=allow protocol=TCP localport=3389

4.3. Disable (close) port on Windows

Method 1: Disable via GUI

Go toInbound Rules

Find the created rule

Right-click →DisableorDelete

Method 2: Delete via CMD

sudo ufw allow 80

netsh advfirewall firewall delete rule name="Open Port 80"

5. Why can't I connect even though the VPS port has been opened?

Cloud firewall not yet opened
Application not running (not listening on port)
Firewall not enabled or misconfigured
Wrong port or wrong protocol
Incorrect domain or IP

At VPTS, we not only provide VPS but also support customers with:

Standard security firewall configuration
Open the correct port for each service (Web, Docker, AI, N8N…)
Performance optimization and quick troubleshooting

CONCLUSION

Through the company's guideVPTSopening and closing ports on a VPS (Linux&Windows) is an important step to ensure the system operates stably and securely. Just properly configure the firewall, open the necessary ports, and ensure the application is active to easily control access and optimize VPS performance effectively.

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