如何让异地伙伴通过FileZilla访问我的Ubuntu服务器？

Absolutely you can set this up for your collaborator—here's a step-by-step guide tailored to your Ubuntu server setup that aligns with how you’re already using FileZilla over SSH:

• Log into your Ubuntu server via SSH (you can use your existing FileZilla SSH connection or a terminal).
• Run the command: sudo adduser collaborator (replace "collaborator" with a username of your choice).
• Follow the prompts to set a password, fill in optional user details, and confirm the account creation.

By default, Ubuntu’s SSH server allows password-based login for new users, but key-based authentication is far more secure—here’s how to set up both options:

Option A: Password-based access (quick but less secure) #

• Ensure password login is enabled in the SSH config:
  1. Open the SSH config file: sudo nano /etc/ssh/sshd_config
  2. Locate the line PasswordAuthentication and set it to yes (remove the # if it’s commented out).
  3. Save and exit (press Ctrl+O, hit Enter, then Ctrl+X), then restart SSH: sudo systemctl restart sshd

Option B: Key-based access (recommended for security) #

• Ask your collaborator to generate an SSH key pair on their local machine: In FileZilla, they can go to Edit > Settings > SFTP > Add key file, or use the ssh-keygen command in their terminal.
• Have them send you their public key file (it ends with .pub).
• On your server, create the .ssh directory for the new user: sudo mkdir /home/collaborator/.ssh
• Set secure permissions for the directory: sudo chmod 700 /home/collaborator/.ssh
• Append their public key to the authorized keys file: sudo nano /home/collaborator/.ssh/authorized_keys (paste the key content here, then save and exit).
• Fix permissions for the authorized keys file: sudo chmod 600 /home/collaborator/.ssh/authorized_keys
• Assign ownership to the new user: sudo chown -R collaborator:collaborator /home/collaborator/.ssh
• (Optional) For extra security, disable password login: Edit sshd_config again, set PasswordAuthentication no, then restart SSH.

Tell your collaborator to configure their FileZilla with these settings:

• Host: Your server’s public IP address or domain name
• Protocol: Select SFTP - SSH File Transfer Protocol
• Logon Type:
  • If using password access: Choose Normal, then enter the username and password you created.
  • If using key-based access: Choose Key file, enter the username, then browse to their private key file.
• Port: Leave as 22 (the default SSH port—use your custom port if you changed it on the server).

To prevent the collaborator from browsing the entire server, you can set up a "chroot jail" to limit them to your website’s root folder (e.g., /var/www/html):

• Edit the SSH config file: sudo nano /etc/ssh/sshd_config
• Add these lines at the end (replace paths and username as needed):

  Match User collaborator
      ChrootDirectory /var/www
      ForceCommand internal-sftp
      AllowTcpForwarding no
      X11Forwarding no
  

• Ensure the chroot directory is owned by root: sudo chown root:root /var/www
• Restart SSH: sudo systemctl restart sshd
• Note: The collaborator will only be able to edit files in subdirectories they have write permissions for—use sudo chown -R collaborator:www-data /var/www/html to grant them access to your website files.

内容的提问来源于stack exchange，提问作者Bryn