OK, this bugzilla report has not gotten much action --
so lets try this list.
I would think that a common installation would involve two types of
btrfs subvolumes: a new subvolume for root ("/") and one or more
existing subvolumes for /home, etc. Anaconda can handle creation of new
subvolumes nicely and adds them to /etc/fstab. However, for existing
subvolumes, you need to specify "--useexisting" on the btrfs command
which specifies the mount point or anaconda crashes saying that the
subvolume already exists .. OK, that makes sense. But, if you then
specify --useexisting, anaconda proceeds BUT the mount point is NOT
added to /etc/fstab.
This problem has existed since Fedora 18 and is still true in Fedora 20
alpha. How about if someone fixes this, explains why it is not
necessary, or explains how to specify reuse of a btrfs mount point? Is
this too much to ask?
I do not like cross posting ... another copy of this message is posted
on the anaconda-devel-list.