When running virt-sysprep on a VM file containing an fstab, with entries with multiple options, it will fail with "guestfsd: error: aug_get: /files/etc/fstab/1/opt: Too many matches for path expression: There are 2 nodes matching /files/etc/fstab/1/opt", or a similar error.
Augeas' aug_get only returns the value for a single node, and will fail with an error if there are multiple matches for the string. In this case, the nodes "/files/etc/fstab/1/opt[1]" and "/files/etc/fstab/1/opt[2]" exists and aug_get /files/etc/fstab/1/opt will match both of these nodes.
It appears that libguestfs does "aug_match /files/etc/fstab/1/opt" to get the nodes for all the options for the first entry (and so on), but it then runs "aug_get /files/etc/fstab/1/opt", which returns an error. I suspect that it's supposed to get the first option instead (/files/etc/fstab/1/opt[1]).
Ubuntu version: Ubuntu 16.04 LTS
libguestfs0 version: 1:1.32.2-4ubuntu2
libguestfs-tools version: 1:1.32.2-4ubuntu2
Additional information:
The image file in question is a qcow2 image file, with Ubuntu 16.04 "xenial" installed.
The partitions present on the qcow2 image are a FAT32 EFI System Partition, and a btrfs root filesystem with two subvolumes: @ (for /), and @home (for /home).
The fstab present on the installation of Ubuntu contains multiple fstab entries with multiple options, e.g. "relatime,subvol=@" for /
Bug still exists as of commit c711b517094375d