Why use an NFS soft mount vs. a hard mount for NameNode storage directories?

This topic contains 0 replies, has 1 voice, and was last updated by  Robert Molina 1 year ago.

  • Creator
    Topic
  • #46791

    Robert Molina
    Moderator

    Use the Network Files System (NFS) soft mount as the NameNode directory to detect potential NFS directory issues. When using an NFS soft mount, the NameNode will generate errors if there are issues with the mounted directory. In contrast, using a hard mount will not generate an error within the NameNode. This is because using an NFS hard mount will cause the NameNode process to continually wait for a response from the NFS server. Thus, an administrator will not be able to determine if there is an issue with the NameNode.

    NOTE: Using a hard mount can cause applications on a linux system to hang, hence NameNode can hang as well. Please do not use hard mounts for Namenode and Datanode data directories.

You must be to reply to this topic. | Create Account

Hortonworks Data Platform
The Hortonworks Data Platform is a 100% open source distribution of Apache Hadoop that is truly enterprise grade having been built, tested and hardened with enterprise rigor.
Get started with Sandbox
Hortonworks Sandbox is a self-contained virtual machine with Apache Hadoop pre-configured alongside a set of hands-on, step-by-step Hadoop tutorials.
Modern Data Architecture
Tackle the challenges of big data. Hadoop integrates with existing EDW, RDBMS and MPP systems to deliver lower cost, higher capacity infrastructure.