It seems [1] has introduced a slight regression in that it tries
by default to pass an empty string to ceilometer-upgrade which
makes it fail:
ceilometer-upgrade: error: unrecognized arguments:
(note there is nothing more on that line)
This patch fixes that by allowing the params to be of any number,
including zero.
Backport to Ussuri.
[1] 3d587409ee068843cfa28710f09f65af48b69367
Change-Id: I989a1dd30d1656b5c1fda7a46abbf5f265fbb72c
Closes-Bug: #1884919
69b8b7a49f