Is it ok to deploy Master services in HA mode but without RAID

[#1]

One of the partner I am working with do not want to use RAID on master nodes.

They are looking for some answers to below questions.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

1) Do you think we can rely on HA for handling service interruptions due to disk failures

2) Will HA failover kick if the drive that has the mount for service configuration files (XML files) fail

3) Will HA failover kick if the drive that has the mount for log files fails

4) If a service uses local storage for metastore, will HA failover kick if the drive that has the mount for metastore fails.

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

What is your opinion on these?

@Chris Nauroth , @sdutta@hortonworks.com, @vnair@hortonworks.com

[#2 · Accepted solution]

This is a bad idea and will be flagged during an architecture review. Master servers must have RAID for production deployments, and we recommend RAID 5 or, more often, 10.

No amount of software HA and failover will address a situation when an OS or primary disk is lost if care wasn't taken of the data in advance. Imagine if HA was a solid solution, but client configuration for the HA mode was saved on a disk which failed, without any replica or a redundant drive.

Master nodes must have RAID arrays for production.