How to Fix SSH Connection Timeout Errors Due to Firewall Rules

✨ Quick Answer

The time limit reached error on port 22 (ssh: connect to host ... port 22: Connection timed out) occurs when the destination server's firewall (typically IPTables or UFW on Ubuntu/Debian) silently drops or blocks incoming network packets on port 22, preventing client authentication.

Quick Diagnostics

Cause

iptables or UFW firewall rules blocking SSH port (22)

Solution

Allow SSH port 22 in firewall: sudo ufw allow 22/tcp

Cause

SSH server daemon not listening on expected IP address

Solution

Check SSH daemon status: sudo systemctl status sshd

The time limit reached error on port 22 (ssh: connect to host ... port 22: Connection timed out) occurs when the destination server's firewall (typically IPTables or UFW on Ubuntu/Debian) silently drops or blocks incoming network packets on port 22, preventing client authentication.

Step-by-Step Solution

1. 1

   Step 1: Diagnose if the SSH port is blocked or closed

   Perform a direct network check towards the server's port from your local terminal to verify if it responds to TCP handshakes:

   BASH Copy

   # Check port 22 (SSH) status on your remote server
   nc -zv 192.168.1.100 22
   

   (If the output returns "Connection timed out" or hangs indefinitely, the port is being blocked by a local or cloud network firewall).

2. 2

   Step 2: Allow SSH traffic in UFW (Uncomplicated Firewall)

   If your server uses UFW, explicitly allow secure remote access and reload kernel rules:

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   # Allow incoming TCP traffic on the default SSH port
   sudo ufw allow 22/tcp
   
   # Enable UFW if inactive, then reload active rules
   sudo ufw enable && sudo ufw reload
   

3. 3

   Step 3: Configure explicit rules in IPTables

   If you do not use UFW or need fine-grained rules in raw IPTables, open port 22 directly in your input chain:

   BASH Copy

   # Accept incoming TCP packets on port 22
   sudo iptables -A INPUT -p tcp --dport 22 -j ACCEPT
   
   # Save the active rules to persist across system reboots
   sudo iptables-save | sudo tee /etc/iptables/rules.v4