1. Used the native FreeBSD support for ext2, with no additional configuration.
External ext2 drive mounted great, used and unmounted 3 times.
How did you mount and unmount the file system? My educated guess: You don't know how you did it, see below.
2. 4th time ext2 external drive mounted with errors. Something about "illegal operation."
We can't debug "something about". We might be able to debug exact error messages. Educated guess: The file system was not actually unmounted cleanly, and now can't be remounted without fsck.
3. Could not cleanly unmount.
Same question: What did it really say, what was the error message? Usually, being unable to unmount is due to a process having an object (file or directory) open on the file system. Commonly, this is a shell that is cd'ed into the file system, holding the current directory open.
4. External ext2 drive is now stuck in read only mode. Could see all files, but everything marked with a padlock.
The standard Unix (Linux and FreeBSD) interface doesn't have padlocks. It has text-based messages. What does the output of "mount" show? What message do you get when you try to explicitly perform a mount command without the ro option? My educated guess: You don't actually know, since you don't know how the mount happens.
Not having much luck using FreeBSD with file systems on external drives.
I'm starting to think maybe they all have issues.
Most other people are capable of using these file systems on external drives.
And that maybe it would be best to stick with FreeBSD's own file systems (UFS and/or ZFS)?
Absolutely the correct conclusion. Using non-native file systems is always dangerous, in particular when using them to write. On FreeBSD, I would use only UFS (the FreeBSD version), ZFS, and (ex-) FAT.
1. Formated external hard drive with UFS2 file system, from a FreeBSD computer, using bsdinstall.
I don't understand. You used bsdinstall to format an external drive to be a UFS file system? The purpose and function of bsdinstall is to install FreeBSD on a computer. Can you maybe tell us what partitioning (gpart...) and mkfs commands you used?
2. Installed pkg fusefs-ufs, fusefs_load="YES" already in /boot/loader.conf.
Why? To use UFS, no fusefs is needed; it is natively built into the kernel. There exists a fusefs-ufs port (and Rust crate), but it is a summer-of-code project, not production.
4. Connected external drive with UFS2 file system to FreeBSD computer, instantly recognized, ...
5. Umounted and remounted external drive 3 or 4 times, same behavior. Instant mounts, read/write works, fast unmount.
How did you mount it? Educated guess: You don't know.
6. On 5th attempt to remount, started throwing same type of errors as ext2/3/4, "invalid command," /etc.,
yet it showed the first level of folders. All other files previously on drive missing (or at least not showing.) command line shows all files missing (or at least not showing.). Drive does not say "read only mode" but it refuses attempted
write operations.[/quote]
Are the directories in the root of the file system there or not? You first say they are (you are using the words "first level of folders", but I'm interpreting it that way), then you say from the command line they are not. Which one is it?
And how did you determine that it is read only or not? What is the output of mount? What are the messages when "it refuses"?
7. And, this is a new one. Now, after rebooting, the Thunar file manager refuses to run. Click to run it, nothing happens.
Now we've done some kind of damage to the operating system.
I have no knowledge of what Thunar does. But it is not part of the operating system, it is a package you installed. I'm pretty certain that the OS itself is not damaged at all. Thunar might have some sort of persistent configuration, and a quick web search shows it to have lots of bugs, so I suspect it to be the problem here. Matter-of-fact, I suspect that the real root cause is that you don't know what you are doing, and just looking at one (buggy) GUI file manager.
Could it be some kind of a hardware problem? The USB port? The drive enclosure?
Seems very unlikely, given that (a) it sometimes works fine, (b) it works great from Linux, and (c) the symptoms are all compatible with file systems being recklessly unmounted, no fsck being performed, and thus being corrupted by the user.
...
Now, with FreeBSD 14.2, upon reinstalling, I noticed that things were auto-mounting.
...
You have not installed or configured an auto-mounter. Your external disks keeps auto-mounting, and you don't even know why. You probably have no idea how the drives are being mounted, with what parameters, what FS types, at what mount points. You are relying on a magic you don't even attempt to understand, even though you know it shouldn't be working.
May I suggest that if you are really interested in writing to external drives, that you sanitize your installation, remove extraneous components (in particular the GUI = DE and all file managers and auto-mounters), and try to reproduce your problems from the command line. And while doing so, record the actual error messages and actual status outputs, not just "something about" and "does not say" and "refuses".