There are
differences between operating systems. For example, on Linux IPV6_V6ONLY
is off by default. When it is off, the following will BindAddress
parameter not work as expected. The bind to IPv6 wildcard address is done
first and this does not allow binding to IPv4 wildcard address
afterwards:
BindAddress ::, 0.0.0.0
If IPV6_V6ONLY
is set to 1, the IPv6 bind will not affect the IPv4 bind and the example
BindAddress will work as expected. On OS X 10.9 it is possible to bind to
IPv4 wildcard address first followed by IPv6 wildcard address. On Windows
IPV6_V6ONLY behaviour is the default.