How to Fix SSH Connection Refused on a Linux Server

ssh: connect to host port 22: Connection refused means the network request reached the host, but nothing accepted the connection on that port. This differs from a timeout, which often points to routing or firewall drops.

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Common Causes

• The SSH daemon is stopped or failed.
• The service listens on a custom port.
• UFW, nftables, or a cloud firewall rejects the connection.
• The hostname points to the wrong server.

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Step 1: Check the SSH Service from the Provider Console

Use the cloud provider’s serial, recovery, or web console so you do not depend on SSH.

# Ubuntu / Debian
sudo systemctl status ssh

# RHEL / Fedora / CentOS
sudo systemctl status sshd

If the service is inactive, inspect its logs and configuration before restarting:

sudo sshd -t
sudo systemctl restart ssh
sudo systemctl enable ssh

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Step 2: Confirm the Listening Port

sudo grep -Ei '^\s*Port' /etc/ssh/sshd_config
sudo ss -lntp | grep ssh

Connect to a custom port explicitly:

ssh -p 2222 user@server_ip

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Step 3: Correct Firewall Rules

sudo ufw status verbose
sudo ufw allow 22/tcp
sudo ufw reload

When using a custom port, allow that port before restarting SSH so you do not lock yourself out.

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Step 4: Audit the Cloud Security Group

Add an inbound TCP rule for the actual SSH port. Restrict the source to your public IP with a /32 mask instead of exposing administrative access to the entire internet.

SSH Error Matrix

Error	Likely cause	Next action
Connection refused	Service stopped or wrong port	Check sshd and listener
Connection timed out	Firewall or route drop	Audit network rules
Permission denied	Key or user mismatch	Check authorized_keys
Host key changed	Server rebuilt or risk	Verify fingerprint before updating