Hi, Please review this patch http://dmitryalexandrov.net/~bgjug/network-interface/webrev.00/
It fixes the problem described in this thread http://mail.openjdk.java.net/pipermail/net-dev/2014-December/008806.html Also in order to setup dummy interface with test values you can use these commands: ip link add dummy0 type dummy ip addr add 10.5.5.1/28 brd 10.5.5.15 dev dummy0 ip addr add 10.6.0.1/23 brd 10.6.1.255 dev dummy0 ip addr add 10.7.0.1/25 brd 10.7.0.127 dev dummy0 The output from NetworkInterface test test/java/net/NetworkInterface/NetParamsTest.java for this interface is: dummy0 : Status: DOWN Hardware Address: 56:ffffffd4:fffffffd:ffffffc2:ffffffec:ffffff82: Loopback: false Point to Point: false Virtual: false Multicast: false MTU: 1500 Bindings: /10.7.0.1/25 [/10.7.0.127] /10.6.0.1/23 [/10.6.1.255] /10.5.5.1/28 [/10.5.5.15] This is the output from Java 1.8.0_25. Same output is produced with existing version of NetworkInterface.c in JDK 9 dummy0 : Status: DOWN Hardware Address: 56:ffffffd4:fffffffd:ffffffc2:ffffffec:ffffff82: Loopback: false Point to Point: false Virtual: false Multicast: false MTU: 1500 Bindings: /10.7.0.1/28 [/10.5.5.15] /10.6.0.1/28 [/10.5.5.15] /10.5.5.1/28 [/10.5.5.15]