Comment 4 for bug 1811682

Here is the oldest BZ relevant to this topic:
https://bugzilla.redhat.com/show_bug.cgi?id=1619387

tl;dr the libibverbs.so line is a harmless warning printed out in newer ovs when this library is not installed (it is used for mellanox stuff but not needed for vanilla ovs).
On a more detailed note, this caused some issues in neutron where any output on stderr would be recognized as failure (now fixed), and we have work in progress to replace CLI parsing by direct DB queries.

Still though, this is just a harmless warning, and the actual error seems to be farther down when running neutron-db-manage:

2019-01-14 13:31:27 | " \"Could not parse rfc1738 URL from string '%s'\" % name)",
2019-01-14 13:31:27 | "sqlalchemy.exc.ArgumentError: Could not parse rfc1738 URL from string ''",