Fix "ssh_init: host does not exist" in FileZilla on Systemd-Based Distros (Ubuntu, Debian, CentOS 8+)

Table of Contents: Introduction Test DNS Resolution Use IP Address in FileZilla Update Systemd DNS Settings Flush DNS Cache Edit Hosts File Restart Network Service Verify Firewall Rules Summary of Fixes

The "ssh_init: host does not exist" error in FileZilla occurs when SSH/SFTP cannot resolve the hostname. This is common on systemd-based distros like Ubuntu, Debian, and CentOS 8+, where DNS settings and network configurations may interfere with hostname resolution.

1. Test DNS Resolution on Systemd-Based Distros

Before troubleshooting SSH in FileZilla, check whether DNS is resolving the hostname correctly.

Test DNS Resolution with systemd-resolve

First, verify that your system has working DNS servers configured:

systemd-resolve --status | grep "DNS Servers"

If DNS servers are listed, your system has a working DNS configuration. If no DNS servers are listed, you'll need to update your DNS settings (see Step 3).

Test Hostname Resolution

Try resolving your FTP/SFTP server hostname using systemd's resolver:

systemd-resolve yourserver.com

Or use the traditional host command:

host yourserver.com

If an IP address is returned, DNS is working correctly. If you see "host not found" or no IP address appears, move to Step 3.

2. Use the IP Address Instead of the Hostname in FileZilla

If DNS is failing, try connecting using the server's IP address instead of the hostname.

Find the IP Address of Your Server

If you don't know your server's IP address, retrieve it using:

dig yourserver.com +short

or

nslookup yourserver.com

Example Output:

192.168.1.10

Use this IP in FileZilla.

Configure FileZilla to Use the IP Address

1. Open FileZilla.
2. Click File > Site Manager.
3. Select your FTP/SFTP connection.
4. Change the Hostname:
   • Instead of yourserver.com, enter 192.168.1.10 (your actual server IP).
5. Click "Connect".

If the connection succeeds, DNS was the issue. You can continue using the IP address, or proceed with the following steps to fix DNS resolution so you can use the hostname.

3. Update Systemd DNS Settings

If DNS resolution fails, you can manually set your system's DNS servers in systemd's configuration.

1. Edit the systemd-resolved configuration file:

   sudo nano /etc/systemd/resolved.conf

2. Find and update these lines (uncomment them if they start with #):

   [Resolve]
   DNS=8.8.8.8 1.1.1.1
   FallbackDNS=8.8.4.4 1.0.0.1
   Domains=~.

3. Save the file (Ctrl+O) and exit (Ctrl+X).
4. Restart the systemd-resolved service:

   sudo systemctl restart systemd-resolved

Now, retry connecting in FileZilla.

4. Flush DNS Cache in Systemd-Based Distros

If you've updated DNS settings, flush the cache to apply changes immediately.

sudo systemd-resolve --flush-caches

Now check again if your hostname resolves:

systemd-resolve yourserver.com

If an IP address appears, DNS is working correctly.

5. Manually Map the Hostname in /etc/hosts

If the hostname still does not resolve, you can manually add it to your system's hosts file.

1. Open the hosts file with root privileges:

   sudo nano /etc/hosts

2. Add this line at the end of the file (replace with your actual IP and hostname):

   192.168.1.10 yourserver.com

3. Save the file (Ctrl+O) and exit (Ctrl+X).

This forces your system to recognize the hostname regardless of DNS status. Now, SSH should recognize the hostname.

6. Restart Network Service

Restart networking to apply all network configuration changes.

sudo systemctl restart networking

For systems using NetworkManager (common on desktops):

nmcli networking off && nmcli networking on

Now retry SSH connection in FileZilla.

7. Verify Firewall Rules

If SSH is being blocked by the firewall, you need to allow it through.

For UFW (Ubuntu/Debian)

sudo ufw allow 22/tcp
sudo ufw reload

For Firewalld (CentOS 8+)

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

Now try connecting again in FileZilla.

Summary of Fixes

By following these steps, FileZilla should connect without the "ssh_init: host does not exist" error!