Decommissioning is process to remove one or multiple datanodes from Hadoop.
To decommission a datanode you need to use following process:
Login to namenode host.
Add follwoing configuration in/home/guest/hadoop-2.5.1/etc/hadoop/hdfs-site.xml
isl-0.15 is required to build GCC with the Graphite loop optimizations. You can download the isl-0.15 from ftp://gcc.gnu.org/pub/gcc/infrastructure/
# bunzip2 isl-015.tar.bz2
# tar -xvf isl-0.15
# ./configure --prefix=/usr/local/isl-0.15 --with-gmp-prefix=/usr/local/gmp-4.3.2
# make && make install
To perform syntax check and dry run for ansible playbook use following command: ansible-playbook -i hosts_file --syntax-check --list-tasks playbook.yml
where, –syntax-check is used to check syntax of a playbook & –list-tasks is to all tasks that are executed.
The DBMS_OUTPUT package is the standard way to "print"
output from PL/SQL. The way DBMS_OUTPUT works is like a
buffer. Your Node.js application code turns on DBMS_OUTPUT buffering, calls some PL/SQL code that puts
text into the buffer, and then later fetches from that buffer. Note:
any PL/SQL code that calls DBMS_OUTPUT runs to completion
before any output is available to the user. Also, other database
connections cannot access your buffer.