UnknownHostException when enabling JMX in Java 8

Question

Using Java 7, I can launch a JVM with JMX enabled without any problems using these properties:

-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.port=8787

If I use Java 8 (Java build 1.8.0_45-b14; Java HotSpot(TM) 64-Bit Server VM build 25.45-b02, mixed mode), I always get an error like this:

java.net.MalformedURLException: Local host name unknown: java.net.UnknownHostException: 185-69-214-74.ded.intelignet.com.br: 185-69-214-74.ded.intelignet.com.br: unknown error

The error also happens if I add this system property:

-Djava.rmi.server.hostname=185.69.214.74

However, I can successfully launch Java 8 if I don't enable JMX.

Why don't I see the same problem under Java 7? What is causing this and what should I do to avoid this error even with JMX enabled?

More details:

$ hostname

mybox

$ hostname -i

185.69.214.74

$ host $(hostname -i)

74.214.69.185.in-addr.arpa domain name pointer 185-69-214-74.ded.intelignet.com.br.

A possible work-around is to edit /etc/hosts to add this line:

185.69.214.74   185-69-214-74.ded.intelignet.com.br

However, I'm not allowed to do this, so I must find another way to solve this problem.

Solution

After debugging class java.net.InetAddress, method getLocalHost, I've seen it calls Inet4AddressImpl.getLocalHostName, which returns "185-69-214-74.ded.intelignet.com.br" when I use '-Djava.net.preferIPv4Stack=true'. If I omit 'java.net.preferIPv4Stack', then InetAddress.getLocalHost calls Inet6AddressImpl.getLocalHostName, which returns "mybox" and the problem goes away.

In other words, 'UnknownHostException' only happens if these conditions are both true:

• -Djava.net.preferIPv4Stack=true
• Java version = 8

So I'll just omit -Djava.net.preferIPv4Stack=true, since I haven't figured out another way of fixing this.

Comments

[ᴠɪɴᴄᴇɴᴛ]

Not using -Djava.net.preferIPv4Stack=true (nor using false for the value or even using java.net.preferIPv6Addresses=true) doesn’t resolve the problem with current versions of Java 8 (build 102+).