Fix "EAI_NONAME" Error in FileZilla (DNS Resolution Issue)

Table of Contents: Understanding the Error Check the FTP Hostname Test DNS Resolution Edit Hosts File Manually Restart Router & Flush DNS Cache Check Firewall & Network Settings Verify FileZilla Site Manager Settings

The "EAI_NONAME - Neither nodename nor servname provided, or not known" error in FileZilla occurs when the FTP client cannot resolve the hostname. This is typically a DNS (Domain Name System) issue, meaning FileZilla is unable to find the FTP server's IP address. This guide focuses specifically on DNS-related solutions for this error.

Understanding the Error

EAI_NONAME is a network error that indicates the system's DNS resolver cannot translate the hostname you provided into a numerical IP address. When FileZilla attempts to connect to "ftp.yourdomain.com", your computer queries DNS servers to get the corresponding IP. If this lookup fails, FileZilla displays the EAI_NONAME error.

Common causes include:

• Incorrect or misspelled hostname in FileZilla
• DNS servers are unreachable or misconfigured on your computer
• The DNS record for your FTP server doesn't exist or hasn't propagated
• Local DNS cache contains outdated or corrupted entries
• Network restrictions blocking DNS queries

Check the FTP Hostname in FileZilla

The first and simplest test is to verify whether the issue is with DNS resolution or a more general connection problem.

1. Open FileZilla
2. Instead of using the hostname (e.g., ftp.yourdomain.com), enter your server's IP address directly in the "Host" field
3. Fill in your username and password
4. Click "Quickconnect"

Interpretation:

• Connection succeeds with IP address: Confirms the FTP server is running and accessible. The problem is specifically DNS resolution.
• Connection fails even with IP address: The problem is not DNS. Check firewall settings, server status, or credentials.

Test DNS Resolution in Command Prompt or Terminal

Use command-line tools to diagnose DNS problems directly.

For Windows

For Linux/macOS

Expected Success: The command returns one or more IP addresses.
Failure Indicators:

• NXDOMAIN: The domain name does not exist in DNS
• SERVFAIL: DNS server failure
• REFUSED: DNS server refused the query
• Timeout: No response from DNS servers

Manually Add the FTP Hostname to Hosts File

If DNS is not working, you can bypass it temporarily by adding an entry to your system's hosts file. This file maps hostnames to IP addresses locally.

For Windows

1. Open Notepad as Administrator (right-click > Run as administrator)
2. Click File > Open
3. Navigate to: C:\Windows\System32\drivers\etc\
4. Change "Text Documents (*.txt)" to "All Files (*.*)"
5. Select the file named hosts (no extension) and open it
6. Add a new line at the bottom:
   192.168.1.10 ftp.yourdomain.com
   Replace 192.168.1.10 with your actual FTP server IP address
7. Save the file (Ctrl+S)
8. Restart FileZilla and try connecting with the hostname

For Linux/macOS

Restart Your Router & Flush DNS Cache

DNS caches at various levels (computer, router, ISP) can hold outdated information.

Flush Local DNS Cache

Windows:

macOS:

Linux (systemd-resolved):

Restart Network Equipment

1. Power off your modem and router
2. Wait 30 seconds
3. Power on the modem first, wait for it to fully initialize
4. Power on the router, wait for it to fully start
5. Test FileZilla connection again

Check Your Firewall & Network Settings

While this is a DNS guide, sometimes firewalls interfere with DNS queries.

Check Windows Firewall

1. Go to Control Panel > System and Security > Windows Defender Firewall
2. Click "Allow an app or feature through Windows Defender Firewall"
3. Click "Change settings" (admin privileges required)
4. Ensure FileZilla is checked for both Private and Public networks
5. If FileZilla isn't listed, click "Allow another app..." and browse to:
   C:\Program Files\FileZilla FTP Client\filezilla.exe

Check Router DNS Settings

1. Log into your router admin panel (usually http://192.168.1.1 or http://192.168.0.1)
2. Navigate to Internet/WAN settings
3. Check the DNS server fields
4. Consider changing to public DNS servers:
   • Google DNS: 8.8.8.8 and 8.8.4.4
   • Cloudflare DNS: 1.1.1.1 and 1.0.0.1
5. Save settings and restart the router

Verify FileZilla Site Manager Settings

Incorrect settings in FileZilla can sometimes cause connection issues.

1. Open FileZilla
2. Click File > Site Manager (or press Ctrl+S)
3. Select your site or create a new one
4. Verify these settings:

   Setting	Recommended Value
   Protocol	FTP - File Transfer Protocol
   Host	ftp.yourdomain.com (or IP if testing)
   Port	21 (standard FTP) or 990 for FTPS
   Encryption	Use explicit FTP over TLS if available
   Logon Type	Normal (requires username/password)
   Transfer Settings	Passive mode (recommended for most networks)

5. Click Connect

Summary of Fixes for "EAI_NONAME" in FileZilla