"Super Heroes" (CC BY-SA 2.0) by Olaf Gradin A lot of work has been done to greatly clarify and enhance various environment variables in the Apache Hadoop shell script code. One of those places was in the usage of various _USER environment variables. Prior to 3.0.0-alpha4 In previous releases, the supported variables were: Name Description HADOOP_SECURE_DN_USER User to… Read More »| Effective Machines
A recent Linux kernel update to workaround CVE-2017-1000366 is causing Apache Hadoop’s secure DataNode (and NFS manager) to crash on startup. (Related discussion from Red Hat and Ubuntu) If your systems are running a variant of Apache Hadoop 3.x, you can take advantage of user functions to workaround the Java Invocation API issue that causes… Read More »| Effective Machines
There’s been a lot of chatter in the Apache Hadoop universe lately over the role of the HDFS audit log. This includes a lot of supposition on the purpose of the original design. This is my recollection of the events that led to its creation. Unfortunately, humans do not come with ECC RAM so apologies… Read More »| Effective Machines