Hello @nasheayahu. I just tried this on both RL 8 & 9 and it works fine, so it must be something on your end. Try importing the key first, then create the repository. (so at this point, I’m suggesting deleting the repository file and starting again from scratch).
Remove the repository:
sudo rm -f /etc/yum.repos.d/webmin.repo
Before continuing, do an upgrade to make sure your system is up-to-date without the repository:
sudo dnf upgrade
Now, import the key first. That’s this step from the instructions. (If you’ve already done this, just try it again to make sure):
wget https://download.webmin.com/jcameron-key.asc
rpm --import jcameron-key.asc
Finally, re-create the webmin repository with the content:
[Webmin]
name=Webmin Distribution Neutral
#baseurl=https://download.webmin.com/download/yum
mirrorlist=https://download.webmin.com/download/yum/mirrorlist
enabled=1
gpgkey=https://download.webmin.com/jcameron-key.asc
gpgcheck=1
Now any time I add a repository, before I actually do the installation steps, I do an upgrade again to read the repository into the system. If it is going to throw an error again, it should do it right here:
sudo dnf upgrade
If the upgrade works without error, now try the installation and see how it goes.
If you still get an error, try the following at the top of your webmin.repo:
baseurl=https://download.webmin.com/download/yum
#mirrorlist=https://download.webmin.com/download/yum/mirrorlist
If that works, then it might be a temporary failure of the mirrorlist.