Fix PuTTY “Network error: Connection timed out” (while noVNC works)

Applies to: LumaDock VPS • Windows PuTTY • Linux/macOS OpenSSH • Any Linux OS

If you can access your VPS via the web console (noVNC) but PuTTY cannot connect, SSH (port 22 by default) is being blocked, not listening, or you are using the wrong IP/port. Follow the steps below in order.

Symptoms

• PuTTY shows: Network error: Connection timed out.
• noVNC / HTML console works and you can log in locally.
• Port checks show SSH (22) as filtered or closed.

Before you start

• Use your VPS public IPv4 address from the LumaDock Client Area.
• Confirm the SSH port. Default is 22 unless you changed it.
• If you use an SSH key with PuTTY, convert it to .ppk using PuTTYgen.

Step 1 — Check from your computer

1.1 Test TCP reachability

Windows (PowerShell):

Test-NetConnection <SERVER_IP> -Port 22

macOS / Linux:

nc -vz <SERVER_IP> 22
# or (if installed)
nmap -Pn -p22 <SERVER_IP>

Interpretation: open = network path OK. filtered/timeout = firewall or routing issue. closed/refused = host reachable but SSH not listening.

1.2 Verify PuTTY settings

• Host Name (IP address): use your VPS IPv4 (e.g., 203.0.113.10).
• Port: 22 (or your custom port).
• Connection type: SSH.
• Optional: force IPv4. In PuTTY, set Connection → Proxy to None.

Step 2 — Check provider/edge firewall rules

In the LumaDock Client Area firewall, make sure inbound SSH is allowed:

• Allow TCP 22 (or your custom SSH port) from 0.0.0.0/0 for testing.
• If you use DDoS filtering, confirm SSH is not blocked.

Step 3 — Fix inside the VPS (via noVNC console)

Log in via noVNC console and run these checks:

3.1 Confirm IP and routing

ip addr
ip route

3.2 Check SSH service

# Ubuntu/Debian
sudo systemctl status ssh || sudo systemctl start ssh

# CentOS/Alma/Rocky
sudo systemctl status sshd || sudo systemctl start sshd

# Check listening socket
sudo ss -lntp | grep :22

3.3 Open firewall inside VPS

Ubuntu/Debian (UFW):

sudo ufw allow 22/tcp
sudo ufw reload

RHEL/Alma/Rocky (firewalld):

sudo firewall-cmd --add-service=ssh --permanent
sudo firewall-cmd --reload

3.4 Validate sshd configuration

sudo grep -E '^(Port|ListenAddress|PasswordAuthentication)' /etc/ssh/sshd_config

If you use a custom port, open it in both the VPS and LumaDock firewalls, then restart SSH:

sudo systemctl restart sshd

3.5 Check login policy

• Default usernames: root (if enabled) or distro-based (ubuntu, debian, rocky).
• Ensure your public key is in ~/.ssh/authorized_keys.

3.6 Fail2ban or intrusion blocks

sudo fail2ban-client status sshd
sudo fail2ban-client set sshd unbanip <YOUR_IP>

Step 4 — Quick fixes

• Open TCP 22 on both the LumaDock firewall and inside the VPS.
• Start and enable the SSH service on boot:

  sudo systemctl enable --now sshd

• Connect using the correct username and port.
• Always test with the IPv4 address first.

Contact LumaDock Support

If you still cannot connect, open a support ticket and include:

• Your VPS IP and SSH port.
• Output of:

  Test-NetConnection <IP> -Port <PORT>   # Windows
  nmap -Pn -p<PORT> <IP>                  # macOS/Linux
  sudo systemctl status sshd
  sudo ss -lntp | grep :<PORT>
  

• Your source IP and approximate time of attempted connection.