I strongly recommend not upgrading to 3.7. Here's my thoughts on Tick Tock releases, copy / pasted from a previous email I wrote on this ML:
3.7 falls under the Tick Tock release cycle, which is almost completely untested in production by experienced operators. In the cases where it has been tested, there have been numerous bugs found which I (and I think most people on this list) consider to be show stoppers. Additionally, the Tick Tock release cycle puts the operator in the uncomfortable position of having to decide between upgrading to a new version with new features (probably new bugs) or back porting bug fixes from future versions themselves. There will never be a 3.7.1 release which fixes bugs in 3.7 without adding new features. https://github.com/apache/cassandra/blob/trunk/NEWS.txt For new projects I recommend starting with the recently released 3.0.9. Assuming the project changes it's policy on releases (all signs point to yes), then by the time 4.0 rolls out a lot of the features which have been released in the 3.x series will have matured a bit, so it's very possible 4.0 will stabilize faster than the usual 6 months it takes for a major release. All that said, there's nothing wrong with doing compatibility & smoke tests against the latest 3.x release as well as 3.0 and reporting bugs back to the Apache Cassandra JIRA, I'm sure it would be greatly appreciated. https://issues.apache.org/jira/secure/Dashboard.jspa Jon On Fri, Sep 23, 2016 at 9:00 AM Khaja, Raziuddin (NIH/NLM/NCBI) [C] < [email protected]> wrote: > Thank you Joaquim for the advice. > > > > I seem to have sent this email with the wrong subject. It should have > been *Upgrading from Cassandra 2.1.12 to 3.7*, but too late now. > > > > The plan is to upgrade from 2.1.12 to 3.7 and to maintain a heterogeneous > cluster only for a short time, while we observe how 3.7 reacts to our > client applications with traffic, then proceed with upgrading all DCs to > 3.7. > > > > In our current installation we are using *memtable_allocation_type: > offheap_objects*. Support for offheap_objects was removed in the 3.0.x > branch and only added back in 3.4+, so an upgrade to 3.0.9 will not be > possible for me unless I change this parameter. > > Still looking to hear from others about upgrade experiences, problems etc. > > -Razi > > > > *From: *Joaquin Casares <[email protected]> > *Reply-To: *"[email protected]" <[email protected]> > *Date: *Friday, September 23, 2016 at 11:41 AM > *To: *"[email protected]" <[email protected]> > *Cc: *"Khaja, Raziuddin (NIH/NLM/NCBI) [C]" <[email protected]> > *Subject: *Re: Upgrading from Cassandra 2.1.12 to 3.0.9 > > > > Hello Razi, > > > > Since you were using a highly stable version of 2.1.x, you may want to > stick with using 3.0.9. 3.7 has introduced many great features, but has not > been as heavily tested in production as 3.0.9. > > > > Running heterogenous clusters, even when using the same major version > (e.g. 3.0.8 and 3.0.9), is never recommended. Running a cluster that spans > major releases, for longer than the timespan of a routine upgrade, is > strongly not advised. > > > > Hope that helps! > > > Joaquin Casares > > Consultant > > Austin, TX > > > > Apache Cassandra Consulting > > http://www.thelastpickle.com > > > > On Fri, Sep 23, 2016 at 8:17 AM, Khaja, Raziuddin (NIH/NLM/NCBI) [C] < > [email protected]> wrote: > > Hello all, > > > > I would like to upgrade my Cassandra cluster from 2.1.12 to 3.7. > > > > I have read the following documentation: > > · > http://docs.datastax.com/en/latest-upgrade/upgrade/cassandra/upgrdCassandra.html > > · https://github.com/apache/cassandra/blob/cassandra-3.7/NEWS.txt > > > > but still had some questions: > > · The upgrdCassandra.html page says : “Upgrade from Cassandra 2.1 > versions later or equal to 2.1.9 directly to Cassandra 3.0.x”, and I am not > sure if this includes 3.x, my question is: Can I upgrade directly to 3.7? > > · Can I run a heterogeneous cluster, with one DC running 2.1.12 > and another DC running 3.7? > > > > Thanks, > > -Razi > > >
