The only Fedora 29 specific instructions that I found are at this link: https://www.if-not-true-then-false.com/2010/install-virtualbox-guest-additions-on-fedora-centos-red-hat-rhel/
Since that link is apparently focused on guest additions, I decided to ignore it.
A year ago, I successfully installed VirtualBox in Fedora 26 by following instructions that were similar to the following link: https://www.if-not-true-then-false.com/2010/install-virtualbox-with-yum-on-fedora-centos-red-hat-rhel/
Since I couldn't find corresponding instructions specifically for Fedora 29, I attempted to follow the same instructions. First, I executed the following command:
dnf install binutils gcc make patch libgomp glibc-headers glibc-devel kernel-headers kernel-devel dkms
Although the command appeared to complete normally, it did show the following message:
Failed to synchronize cache for repo 'virtualbox', ignoring this repo.
I then executed:
dnf install VirtualBox-5.2
Fedora 29 - x86_64 - VirtualBox Failed to synchronize cache for repo 'virtualbox', ignoring this repo. Last metadata expiration check: 0:05:45 ago on Sat 17 Nov 2018 03:40:42 PM PST. No match for argument: VirtualBox-5.2 Error: Unable to find a match
I am not sure if this is relevant, but just out of curiosity, I executed
cd / find -type f -iname "virtualbox.*" find -type f -iname "virtualbox*"
It seems as if Fedora 29 (complete install, not upgrade) is installing some VirtualBox Guest-Addition rpm's. I will post a separate query re what I should do to install guest additions once I've got VirtualBox installed. I mention it in this posting only as it might relate to my specific problem.
Similarly, I'm unsure whether the following link is relevant: VirtualBox failed to install in Fedora 26
In that link, I made a mistake and got UnixSE responses about backing out my mistake before I did the install.
Why am I getting the message "Failed to synchronize cache for repo virtualbox"?
Why am I getting the message "No match for argument: VirtualBox-5.2"?
Do I need to back anything out before I proceed with the install?
How do I install VirtualBox in Fedora 29.