(also DNS configuration failure)
Unknown host definition
An unknown host refers to an error message that shows up when a device cannot identify another system’s hostname or domain name. It typically occurs due to a misconfiguration in the DNS. Since the unknown host isn’t a security risk by itself, hackers often misuse it to exploit the DNS misconfiguration and attack the users’ devices. In such a situation, users must immediately eliminate the data breach to keep their sensitive information, such as login credentials, bank accounts, and financial data, secure.
See also: DNS redirection, access control entry
When does an unknown host occur?s
- Incorrect hostname. If the user misspells the hostname or it is otherwise incorrect, the DNS will fail to resolve it.
- DNS server issues. The DNS server might be experiencing problems or temporary outages.
- Connectivity problems. If the user faces connectivity issues, such as a poor internet connection or misconfigured network settings, it can interfere with the DNS resolution process.
- Expired or non-existent domain. The domain the user tries to access might have expired or been removed, meaning the DNS system no longer has it.
How can an unknown host be resolved?
- Double-check the hostname to ensure you have spelled it correctly, that it is complete, and without typos.
- Check for and resolve connectivity issues on your device or network.
- Try to access the domain from another device or a different network.
- Clear DNS to resolve issues related to stale or outdated DNS entries.
- Change your DNS server if you suspect the issue might be related.
- Ensure your system’s host file contains no incorrect or outdated entries.
- Check firewall and security software to ensure your measures don’t block access to the domain you’re trying to reach.
- Contact your ISP or network administrator if nothing else works.