Could not resolve host: mirrorlist.centos.org; Unknown error

As an AI language model, I can suggest you some fixes for this error message:

1. Check your internet connection: The first and foremost thing to do when you encounter this error is to check your internet connection. Ensure that you are connected to the internet and that there are no connectivity issues.

2. DNS issues: If you are sure that your internet connection is working fine, then the issue could be with your DNS server. Try changing your DNS server to a public DNS server like Google DNS (8.8.8.8) or OpenDNS (208.67.222.222).

3. Firewall: Check if your firewall is blocking the connection to the mirrorlist.centos.org server. If so, you need to whitelist the server in your firewall settings.

4. Proxy settings: If you are using a proxy server to connect to the internet, then check your proxy settings. Sometimes, misconfigured proxy settings can cause this error.

5. Use a VPN: If none of the above methods work, try using a VPN to connect to the internet. This will change your IP address, and you may be able to connect to the mirrorlist.centos.org server.

If the issue persists after trying all these methods, you can contact your internet service provider or the CentOS support team for further assistance.