Comment 50 for bug 1869075

So blockdev -> symlink conversion did happen:
 Found invalid device mapper mp path: /dev/mapper/mpatha, removing
 del_file: removed /dev/mapper/mpatha
 multipath: regenerating symlink for /dev/mapper/mpatha (/dev/dm-0)
 Running command ['udevadm', 'trigger', '--subsystem-match=block', '--action=add', '/sys/class/block/dm-0'] with allowed return codes [0] (capture=False)
 Running command ['udevadm', 'settle', '--exit-if-exists=/dev/mapper/mpatha'] with allowed return codes [0] (capture=False)
 TIMED udevadm_settle(exists='/dev/mapper/mpatha'): 0.293
 Failed to regenerate udev symlink /dev/mapper/mpatha
 Running command ['pvscan', '--config', 'devices{ filter = [ "a|/dev/mapper/mpath.*|", "r|.*|" ] }'] with allowed return codes [0] (capture=True)
 Running command ['vgscan', '--mknodes', '--config', 'devices{ filter = [ "a|/dev/mapper/mpath.*|", "r|.*|" ] }'] with allowed return codes [0] (capture=True)
 Running command ['vgchange', '--activate=y', '--config', 'devices{ filter = [ "a|/dev/mapper/mpath.*|", "r|.*|" ] }'] with allowed return codes [0] (capture=True)
 Running command ['udevadm', 'settle'] with allowed return codes [0] (capture=False)
 TIMED udevadm_settle(): 0.028
 Loading kernel module bcache via modprobe
 Running command ['modprobe', '--use-blacklist', 'bcache'] with allowed return codes [0] (capture=False)
 Loading kernel module zfs via modprobe
 Running command ['modprobe', '--use-blacklist', 'zfs'] with allowed return codes [0] (capture=False)
 zfs filesystem is not supported in this environment
 Generating device storage trees for path(s): ['/dev/mapper/mpatha', '/dev/mapper/mpatha-part1']
 finish: cmd-install/stage-partitioning/builtin/cmd-block-meta/clear-holders: FAIL: removing previous storage devices

However, now it doesn't like the next thing:

           File "/snap/subiquity/1773/lib/python3.6/site-packages/curtin/block/__init__.py", line 396, in get_blockdev_for_partition
             raise OSError("%s had no syspath (%s)" % (devpath, syspath))
         OSError: /dev/mapper/mpatha had no syspath (/sys/class/block/mpatha)
         /dev/mapper/mpatha had no syspath (/sys/class/block/mpatha)

And i'm not sure how or why that is.