Cassandra 2.1 & # 8594; 3.0 update restrictions

Question

I am trying to understand the limitations of updating from / to different versions of cassandra.

On the one hand, Cassandra docs http://docs.datastax.com/en/upgrade/doc/upgrade/cassandra/upgradeC_c.html

they say: "Limitations of Cassandra 3.0.x: updating versions of Cassandra 2.1 is greater than or equal to 2.1.9 ...", and I understand that "you could not upgrade to 3.0 from 2.1.8 and to 2.1. * versions."

On the other hand, there are no restrictions on upgrading, say, 2.1.8 (version to 2.1.9) to 2.1.11 (grater then version 2.1.9), in particular, 2.1.8-> 2.1.11 updating does not require updating sstables.

So, can someone explain why it is possible to upgrade from 2.1.9 to 3.0, but not from 2.1.8 to 3.0?

Answer 1

Documents restrict you from upgrading from earlier versions 2.1 to 3.0, because bug fixes and stability improvements in later versions 2.1, which affect updates, have been fixed.

The best practice is to switch to the latest patch in your branch before updating the main version. I.E. go to the latest 2.1.x and then go to 3.0.

Note: 3.0.0 fell last night, and it is very early in its release. Before upgrading your instance, be sure to carefully test the qa environment and carefully monitor the upgrade documents.