In OCP when the OVS pod starts up it logs:

...
Starting ovsdb-server.
PMD: net_mlx4: cannot load glue library: libibverbs.so.1: cannot open shared object file: No such file or directory
PMD: net_mlx4: cannot initialize PMD due to missing run-time dependency on rdma-core libraries (libibverbs, libmlx4)
net_mlx5: cannot load glue library: libibverbs.so.1: cannot open shared object file: No such file or directory
net_mlx5: cannot initialize PMD due to missing run-time dependency on rdma-core libraries (libibverbs, libmlx5)
Configuring Open vSwitch system IDs.
Enabling remote OVSDB managers.
Inserting openvswitch module.
PMD: net_mlx4: cannot load glue library: libibverbs.so.1: cannot open shared object file: No such file or directory
PMD: net_mlx4: cannot initialize PMD due to missing run-time dependency on rdma-core libraries (libibverbs, libmlx4)
net_mlx5: cannot load glue library: libibverbs.so.1: cannot open shared object file: No such file or directory
net_mlx5: cannot initialize PMD due to missing run-time dependency on rdma-core libraries (libibverbs, libmlx5)
Starting ovs-vswitchd.
...


Often, when people are having networking problems, they start looking at logs, find this, and decide that this means that OVS is broken and that's their problem.

These errors should either go away, or else be suppressable via some command-line flag or something, or else be rewritten to look more like helpful notes and less like errors.