Customer encountered a SEVERE log message from FD_HOST without stack trace. 2016-11-02 15:55:52,134 SEVERE [org.jgroups.protocols.FD_HOST] (Timer-11,node311-2147) node311-2147: ping command failed: java.lang.NullPointerException It is not a failure of InetAddress.isReachable(), it is a NPE somewhere in the PingTask thread. The stack trace is missed due to a coding error, which is addressed in the upstream by JGRP-2144. Backport it to JDG 6.6.z which may come.
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