Sending 0.0.0.0 doesn't make sense
Today I learned (2018-07-21)
While I've grown used to specifying 0.0.0.0 as the listening address for servers, I got bitten yesterday and realized the dangers of this practice.
If the listening address of a server ever needs to be communicated to others
(as is the case with clustered systems), configuring
0.0.0.0 will lead to bad
things happening. That is: other servers, having learned that your address is
0.0.0.0:SOMEPORT, will attempt to connect and fail.
The RFC states clearly:
This host on this network. MUST NOT be sent, except as a source address as part of an initializatioan procedure by which the host learns its own IP address.