Are you getting this error when trying to connect to a site/domain/service and then you checked your router/nameserver's logs to see what's wrong?
You may see something like this:
named[3025898]: REFUSED unexpected RCODE resolving
This is not usually an error with named or bind, at least not on your end but NORMALLY this is an issue with the remote nameserver.
A lot of times this is a misconfigured remote nameserver. A classi........
Are you getting this error in CentOS 8 when trying to use yum to install a package?
Error: Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist
What we need to do is not use the automatic mirror list and manually set the base URL
Solution
sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS*
sed -i 's%#baseurl=http://mirror.centos.org%baseurl=........