Reid Linnemann wrote in #note-2:
Do we want to cut the cord on UFS and just be done with it?
UFS is OK and not in question here, the problem is gmirror. If a user thinks they need gmirror for some reason or another they would have to install an older version and upgrade. They already haven't been able to create a new gmirror since 2.3 or earlier, reinstalling on gmirror just happened to work in the last iteration of the installer but doesn't any longer.
I was able to get this to work today by deleting and re-creating the UFS partition:
* Highlight the UFS partition
* Choose **Delete**
* Choose **Create**
* Arrow down to the mountpoint field
* Set the mountpoint to ``/``
* Press ``Tab``
* Choose **OK**
* Choose **Finish**
* Choose **Commit**
It also works if you delete the BSD parent (contains both the UFS and swap partitions) and then manually make a new "freebsd" type partition and then inside that, a new "freebsd-ufs" mounted at / plus a "freebsd-swap" partition.
"Auto" doesn't work, nor does installing on top of the old partitions, but the above workaround may be sufficient for anyone still needing to use gmirror in this day and age.
For most people needing a mirror, ZFS is the way to go at this point.
If it's easy to fix 'auto' in the installer we could maybe do that, but I don't see a point to putting in a lot of work here for gmirror.
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