Hi, Please find below a fix for: 8241336: Some java.net tests failed with NoRouteToHostException on MacOS with special network configuration https://bugs.openjdk.java.net/browse/JDK-8241336
webrev: http://cr.openjdk.java.net/~dfuchs/webrev_8241336/webrev.01/index.html The crux of the issue is that on some macOS hardware/OS versions we get network interfaces that look like regular ethernet interfaces though they are not. Picking them up while testing make some tests fail. Most of these tests were already relying on the NetworkConfiguration test library class - which has now been updated to skip these problematic interfaces. I have heuristically observed that these interfaces seemed to only have one link-local IPv6 address, while the other regular interfaces had at least one IPv4, or one non link-local IPv6. That seems to be the only observable difference. The fix also contains some code for AdaptorMulticasting.java aim at better diagnosing (and possibly fixing?) JDK-8238516 [1] - I might close JDK-8238516 as a duplicate of JDK-8241336 if the issue doesn't reproduce. best regards, -- daniel [1] https://bugs.openjdk.java.net/browse/JDK-8238516