[jboss-jira] [JBoss JIRA] Updated: (JBAS-8741) Linux multicast issue using IPv4 addresses and IPv6 stack

Linux multicast issue using IPv4 addresses and IPv6 stack ---------------------------------------------------------- Key: JBAS-8741 URL: https://issues.jboss.org/browse/JBAS-8741 Project: JBoss Application Server Issue Type: Bug Security Level: Public(Everyone can see) Components: Integration Affects Versions: 6.0.0.M4 Environment: Linux only Reporter: Richard Achmatowicz Assignee: Shelly McGowan Fix For: TBD-6.x When starting the AS, we have the following three possible combinations of addresses / stacks: (i) IPv4 addresses with IPv4 stack (java.net.preferIPv4Stack=true) (ii) IPv6 addresses with IPv6 stack (java.net.preferIPv4Stack=false, java.net.preferIPv6Addresses=true) (iii) IPv4 addresses with IPv6 stack ( java.net.preferIPv4Stack=false, java.net.preferIPv6Addresses=false) The stack preference is specified by defining the above system properties; the addresses are specified as inputs to the -b and -u options of run.sh. Many versions of the AS force an IPv4 stack by setting java.net.preferIPv4Stack=true in run.sh when on Linux. There is an issue associated when using the combination IPv4 address / IPv6 stack. The issue is made up of two facts: Fact 1: When we initlaise a multicast socket for group communication, we can initialise it in one of two ways: (i) binding the multicast socket to a multicast address and port (known as "binding to mulicast") (ii) binding a multicast socket to a port only When using an IPv4 address on an IPv6 socket, we cannot bind to multicast. Fact 2: On LInux, there is a known problem, the promiscuous traffic problem, wherein if we have clusters X and Y running, cluster X can see and be influenced by messages from cluster Y, even if the multicast address they use are different. The promiscuous traffic problem can be solved on Linux by binding to multicast. Binding to multicast is not required by other operating systems. Problem: when running with an IPv4 multicast address on an IPv6 stack on Linux, we cannot bind to multicast, and so we have the promiscuous traffic problem oif we use this address / stack combination.