O'Reilly logo

Hadoop 2.x Administration Cookbook by Gurmukh Singh

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Promoting Secondary Namenode to Primary

In this recipe, we will cover how to promote Secondary Namenode to be Primary Namenode.

In production, Datanodes will never talk to the Secondary and only the Primary node knows about the data block mappings. In a non-HA setup, if the Primary Namenode fails, there will be outage, but we can still reduce the downtime by quickly promoting the Secondary to be Primary.

Getting ready

For this recipe, make sure you have completed the previous recipe on Secondary Namenode configuration and have a running Secondary Namenode.

How to do it...

  1. Connect to the master2.cyrus.com master node and switch to user hadoop.
  2. The first thing is to check the seen_txid file under location /data/secondary/current/, to make sure until what ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required