https://github.com/modcluster/mod_cluster/blob/main/core/src/main/java/org/jboss/modcluster/advertise/impl/DatagramChannelFactoryImpl.java#L29-L33

• On BSD-like systems (e.g. OS X) we also need to bind the DatagramChannel to the multicast address. If httpd with
• mod_proxy_cluster (which is bound to the multicast address) is running on the same system, the AdvertiseListener
• would not be able to bind to any address (i.e. only binding to the port without the address) because JDK does not
• expose SO_REUSEPORT as a socket option which would be required for this to work. This is to be supported since JDK 9.
• See {@link <a href="https://bugs.openjdk.java.net/browse/JDK-6432031">JDK-6432031</a>}

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