How to do an OS upgrade on cloudera cluster from Redhat 6 to Redhat 7

[#1]

We have few 100+ node CDH clusters running on Redhat 6.5. What is the process to upgrade the entire cluster from Redhat 6.5 to Redhat 7?

[#2]

@rbodolla,

If you are referring to upgrading in place, in general:

- Follow RedHat instructions for upgrading OS in place: 

https://access.redhat.com/solutions/637583

- Install el7 CM/agent/daemon packages on the host after upgraded

- ensure el7 parcels are available for download/distribution.

Depending on your needs, you may want to decommission the host so that blocks are copied to another node (HDFS).  I would recommend that if you are undertaking this procedure, you plan well and also do a test by adding a node or testing with one as a trial.  There are bound to be small issues in various places.

I've never done it myself, so if anyone else has experience, it would be good to hear from them.

-Ben

[#3]

For posterity, I will helpfully refer to the Cloudera documentation on the topic.

(Good work docs folks.  I love the evironment customization.)