Android notes

Socket connection issue in Android emulator

An Ice application that attempts to connect to an invalid address can generate "spurious wakeup" messages in logcat when running under an emulator for Android 4.2 or later. This issue does not occur on hardware devices, however you can still experience lengthy delays before receiving an exception. As a defensive measure, it is a good idea to always set reasonable timeouts on your proxies to avoid unexpected delays.

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Java notes

IceGrid Admin GUI

The IceGrid graphical administrative utility can be used with Java7 or Java8, however the metrics graph feature is only available when running with JavaFX.

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SSL issues in Java

Anonymous Diffie Hellman ciphersuites

Recent versions of Java7 and Java8 require low-strength ADH ciphersuites to be disabled when using TLS 1.0. It is no longer sufficient to use this IceSSL configuration:

IceSSL.Ciphers=NONE (DH_anon)
IceSSL.VerifyPeer=0

We recommend using this setting instead:

IceSSL.Ciphers=NONE (DH_anon.*AES)
IceSSL.VerifyPeer=0

Entropy pool causes hangs

When using the Ice for Java SSL plug-in (IceSSL), you may experience occasional hangs. The most likely reason is that your system's entropy pool is empty. If you have sufficient system privileges, you can solve this issue by editing the file java.home/jre/lib/security/java.security and changing it to use /dev/urandom instead of /dev/random. If you do not have permission to modify the security file, you can also use the command-line option shown below:

java -Djava.security.egd=file:/dev/urandom MyClass ...

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IPv6 hang in Java

On systems with IPv6 enabled, you may experience occasional hangs the first time an Ice object adapter is activated within a JVM. A work-around is to disable IPv6 support by setting the Java property java.net.preferIPv4Stack to true. For example:

java -Djava.net.preferIPv4Stack=true MyClass ...

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SLES 12 notes

OpenJDK 1.7.0

We do not recommend using OpenJDK 1.7.0_85 on SLES 12. The IceBox/configuration test fails with an unexpected java.io.IOException exception from the selector implementation when run with SSL. The Oracle and IBM JDKs do not exhibit this issue and should be used for Java applications on SLES.

Windows notes

Windows users should be aware of the following issues.

Anti-Virus when testing WebSocket

If your anti-virus intercepts http traffic on localhost, a number of tests in the Ice test suite may fail due to timeouts when running the test suite with the ws (WebSocket) protocol. The work-around is to disable the "web access protection" feature of the anti-virus entirely or at least for localhost (127.0.0.1).

Multicast and Windows Store Apps

Network isolation for Windows Store Apps blocks multicast datagrams on the loopback interface. As a result, IceDiscovery and IceLocatorDiscovery won't be able to discover peers listening on the loopback interface.

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