FULL PRODUCT VERSION :
java version "1.8.0_51"
Java(TM) SE Runtime Environment (build 1.8.0_51-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.51-b03, mixed mode)


ADDITIONAL OS VERSION INFORMATION :
Linux alainodea-xps-l521x 3.13.0-46-generic #79-Ubuntu SMP Tue Mar 10 20:06:50 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.3 LTS"

A DESCRIPTION OF THE PROBLEM :
I think I have identified a regression in network error handling from Java 7 to Java 8.

In Java 7, attempts to resolve a host unknown to the DNS server cause an UnknownHostException stating "Name or service not known".

In Java 8, attempts to resolve a host unknown to the DNS server cause an UnknownHostException stating "unknown error".

Possible root cause:
It appears that Java 7 had initialization that allowed the gai_strerror_ptr function pointer to be correctly initialized:
http://hg.openjdk.java.net/jdk7/jdk7/jdk/file/9b8c96f96a0f/src/solaris/native/java/net/net_util_md.c#l398

However, I cannot find equivalent initialization in JDK 8:
http://hg.openjdk.java.net/jdk8/jdk8/jdk/file/687fd7c7986d/src/solaris/native/java/net/net_util_md.c

REGRESSION.  Last worked in version 7u80

ADDITIONAL REGRESSION INFORMATION: 
java version "1.7.0_80"
Java(TM) SE Runtime Environment (build 1.7.0_80-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode)

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Create a file called InetAddressGetAllByName.java with the content from the source code I have listed on this case

2. Compile InetAddressGetAllByName.java:
javac InetAddressGetAllByName.java

3. Run InetAddressGetAllByName
java InetAddressGetAllByName

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The following is the 

Exception in thread "main" java.net.UnknownHostException: doesnotexist.example.com: Name or service not known
	at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
	at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:901)
	at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1295)
	at java.net.InetAddress.getAllByName0(InetAddress.java:1248)
	at java.net.InetAddress.getAllByName(InetAddress.java:1164)
	at java.net.InetAddress.getAllByName(InetAddress.java:1098)
	at InetAddressGetAllByName.main(InetAddressGetAllByName.java:7)
ACTUAL -
Exception in thread "main" java.net.UnknownHostException: doesnotexist.example.com: unknown error
	at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
	at java.net.InetAddress$2.lookupAllHostAddr(InetAddress.java:928)
	at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1323)
	at java.net.InetAddress.getAllByName0(InetAddress.java:1276)
	at java.net.InetAddress.getAllByName(InetAddress.java:1192)
	at java.net.InetAddress.getAllByName(InetAddress.java:1126)
	at InetAddressGetAllByName.main(InetAddressGetAllByName.java:7)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Arrays;
public class InetAddressGetAllByName {
    public static void main(String[] args) throws UnknownHostException {
        System.out.println(Arrays.toString(InetAddress.getAllByName("doesnotexist.example.com")));
    }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Use filtered system call tracing to determine actual causes when this happens.