Support Questions

Find answers, ask questions, and share your expertise
Announcements
Celebrating as our community reaches 100,000 members! Thank you!

What is active and passive NameNode in Hadoop?

avatar
New Contributor

What is the need of passive NameNode in Hadoop?

1 ACCEPTED SOLUTION

avatar

There is no such thing as a "passive" NameNode. Are you asking about the HA or non-HA configuration?

  1. In an HA configuration, there is
    1. Active NameNode that serves user requests.
    2. Standby NameNode that generates periodic checkpoints. It can also take over the role of the Active if the previously active NameNode dies or becomes unresponsive.
  2. In a non-HA configuration
    1. Primary NameNode that serves user requests.
    2. Secondary NameNode that generates periodic checkpoints. A secondary NameNode can never become the primary.

The terminology is unfortunately confusing.

View solution in original post

3 REPLIES 3

avatar
Expert Contributor

The passive NameNode can be used in high availability configurations, to prevent single point of failure: https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.4/bk_hadoop-high-availability/content/ch_HA-N....

avatar
Expert Contributor

avatar

There is no such thing as a "passive" NameNode. Are you asking about the HA or non-HA configuration?

  1. In an HA configuration, there is
    1. Active NameNode that serves user requests.
    2. Standby NameNode that generates periodic checkpoints. It can also take over the role of the Active if the previously active NameNode dies or becomes unresponsive.
  2. In a non-HA configuration
    1. Primary NameNode that serves user requests.
    2. Secondary NameNode that generates periodic checkpoints. A secondary NameNode can never become the primary.

The terminology is unfortunately confusing.