The most common and safe way to connect to a Linux server is to use SSH. 1. Ensure that the server IP or domain name, user name, port (default 22) and authentication method (password or key); 2. Linux/macOS users use the ssh username@hostname_or_ip -p port command to connect through the terminal. If it is the default port, the -p parameter can be omitted; 3. Windows users can use OpenSSH or graphical interface tool PuTTY, enter the server address and port, and then click "Open" to connect; 4. It is recommended to use SSH key to log in to improve security and convenience. Generate a key through ssh-keygen and upload the public key to the server to achieve password-free login. When encountering connection problems, you should check the network, firewall, permissions and other settings.

The most common and safest way to connect to a Linux server is to use SSH (Secure Shell). As long as you know the IP address and login credentials of the target server, the whole process is actually very simple.

Make sure you have the necessary information

Before you start, you need to confirm the following:

• The server's IP address or domain name : for example 192.168.1.100 or example.com
• Username : such as root or ubuntu
• Port number (default is 22) : If it is not the default port, it needs to be specified specifically
• Authentication method : password login or key login?

If you are connecting to a server for the first time, the system may prompt you to confirm the host fingerprint and enter yes to continue.

Connect using command line (Linux/macOS)

Most Linux distributions and macOS come with SSH clients. Open the terminal and enter the following command:

 ssh username@hostname_or_ip -p port

For example:

 ssh ubuntu@192.168.1.100 -p 22

If the port is the default 22, -p parameter can be omitted:

 ssh ubuntu@192.168.1.100

You will be prompted to enter your password (if it is a password to log in), and after entering it correctly, you can enter the server.

Windows users can use PuTTY or OpenSSH

Windows 10 and above usually have the OpenSSH client installed, and you can operate it directly using the command line, just like Linux/macOS.

If not, you can download and install OpenSSH for Windows or use the graphical interface tool PuTTY:

1. Download and run PuTTY
2. Fill in the server address in the "Host Name (or IP address)" column
3. The default port is 22, if not, please modify it
4. Click "Open" to start the connection
5. After the terminal appears, enter the user name and password

PuTTY is more suitable for beginners who are not very familiar with the command line.

Using SSH keys is safer and more convenient

If you often connect to a certain server, it is recommended to use an SSH key pair to log in:

1. Generate a key locally:

    ssh-keygen -t rsa -b 4096

   Follow the prompts, the default path is ~/.ssh/id_rsa

2. Upload the public key to the server:

    ssh-copy-id username@server_ip

3. You can log in directly when you connect in the future without entering a password

This method is not only safer, but also saves time every time you enter your password.

---

Basically that's it. As long as the network connection, account password or key is fine, the connection process will not be too complicated, but there are many places where errors are prone to details, such as firewall restrictions, port blockage, permission settings, etc. If you encounter problems, you can check them from these aspects.

The above is the detailed content of How to connect to a Linux server using SSH. For more information, please follow other related articles on the PHP Chinese website!