preferIPv6Addresses and preferIPv4Stack System Properties are Mishandled in the Config -------------------------------------------------------------------------------------- Key: WFCORE-4699 URL: https://issues.jboss.org/browse/WFCORE-4699 Project: WildFly Core Issue Type: Bug Components: Server Affects Versions: 10.0.0.Final Environment: * JBoss EAP 7.1/7.2 * Interface attached to port 0.0.0.0 * Red Hat Enterprise Linux 7 * IPv6 disabled in the kernel sysctl -w net.ipv6.conf.all.disable_ipv6=1 sysctl -w net.ipv6.conf.default.disable_ipv6=1 * System properties -Djava.net.preferIPv4Stack=false -Djava.net.preferIPv6Addresses=true Reporter: Teresa Miyar Gil Assignee: Teresa Miyar Gil Priority: Major Labels: ipv6, startup Error is thrown on startup. Caused by: java.net.SocketException: Protocol family unavailable at sun.nio.ch.Net.bind0(Native Method) at sun.nio.ch.Net.bind(Net.java:433) at sun.nio.ch.Net.bind(Net.java:425) at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:223) at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74) at org.xnio.nio.NioXnioWorker.createTcpConnectionServer(NioXnioWorker.java:179) at org.xnio.XnioWorker.createStreamConnectionServer(XnioWorker.java:310) at io.undertow.protocols.ssl.UndertowXnioSsl.createSslConnectionServer(UndertowXnioSsl.java:301) at org.wildfly.extension.undertow.HttpsListenerService.startListening(HttpsListenerService.java:127) The customer ships a turn key solution that has the two system properties set: -Djava.net.preferIPv4Stack=false -Djava.net.preferIPv6Addresses=true because they are needed for some cases for customers running IPv6, but others want to harden their systems by disabling IPv4. This works on JBoss EAP 6, but it throws the error on JBoss EAP 7 on the same version of Java. Furthermore, adding just Djava.net.preferIPv4Stack=false has the same issue, even though it the default value, while leaving it off starts. This appears to be related to controller/src/main/java/org/jboss/as/controller/interfaces/OverallInterfaceCriteria.java#pruneIPTypes where if both properties are null, it leaves the set of candidate addresses alone, but it either are set, it strips out all IPv4 addresses.