This actually means if you *DON'T* use vnodes, you should be careful to set num_tokens in the cassandra.yaml when upgrading, since the default cassandra.yaml is to have vnodes enabled. You should ignore these instructions if you already have a vnodes-enabled cluster, and set num_tokens accordingly.
These transition instructions are leftovers from 1.2 to 2.0 upgrade, when vnodes became the default, and are indeed a bit confusing now from the 2.0 to 2.1 upgrade, so I'm copying the docs team to make that a bit more clear (I believe this excerpt is a bit confusing: "In Cassandra 2.0.x, virtual nodes (vnodes) are enabled by default. Disable vnodes in the 2.0.x version before upgrading"). 2015-11-23 21:22 GMT-02:00 Sebastian Estevez <sebastian.este...@datastax.com >: > If your cluster does not use vnodes, disable vnodes in each new >> cassandra.yaml > > > If your cluster *does* use vnodes do *not* disable them. > > All the best, > > > [image: datastax_logo.png] <http://www.datastax.com/> > > Sebastián Estévez > > Solutions Architect | 954 905 8615 | sebastian.este...@datastax.com > > [image: linkedin.png] <https://www.linkedin.com/company/datastax> [image: > facebook.png] <https://www.facebook.com/datastax> [image: twitter.png] > <https://twitter.com/datastax> [image: g+.png] > <https://plus.google.com/+Datastax/about> > <http://feeds.feedburner.com/datastax> > <http://goog_410786983> > > > <http://www.datastax.com/gartner-magic-quadrant-odbms> > > DataStax is the fastest, most scalable distributed database technology, > delivering Apache Cassandra to the world’s most innovative enterprises. > Datastax is built to be agile, always-on, and predictably scalable to any > size. With more than 500 customers in 45 countries, DataStax is the > database technology and transactional backbone of choice for the worlds > most innovative companies such as Netflix, Adobe, Intuit, and eBay. > > On Mon, Nov 23, 2015 at 5:55 PM, Robert Wille <rwi...@fold3.com> wrote: > >> I’m wanting to upgrade from 2.0 to 2.1. The upgrade instructions at >> http://docs.datastax.com/en/upgrade/doc/upgrade/cassandra/upgradeCassandraDetails.html >> has >> the following, which leaves me with more questions than it answers: >> >> If your cluster does not use vnodes, disable vnodes in each new >> cassandra.yaml before doing the rolling restart. >> In Cassandra 2.0.x, virtual nodes (vnodes) are enabled by default. >> Disable vnodes in the 2.0.x version before upgrading. >> >> 1. In the cassandra.yaml >> >> <http://docs.datastax.com/en/upgrade/doc/upgrade/cassandra/upgradeCassandraDetails.html#upgradeCassandraDetails__cassandrayaml_unique_7> >> file, >> set num_tokens to 1. >> 2. Uncomment the initial_token property and set it to 1 or to the >> value of a generated token >> >> <http://docs.datastax.com/en/cassandra/2.1/cassandra/configuration/configGenTokens_c.html> >> for >> a multi-node cluster. >> >> >> It seems strange that vnodes has to be disabled to upgrade, but whatever. >> If I use an initial token generator to set the initial_token property of >> each node, then I assume that my token ranges are all going to change, and >> that there’s going to be a whole bunch of streaming as the data is shuffled >> around. The docs don’t mention that. Should I wait until the streaming is >> done before proceeding with the upgrade? >> >> The docs don’t talk about vnodes and initial_tokens post-upgrade. Can I >> turn vnodes back on? Am I forever after stuck with having to have manually >> generated initial tokens (and needing to have a unique cassandra.yaml for >> every node)? Can I just set num_tokens = 256 and comment out initial_token >> and do a rolling restart? >> >> Thanks in advance >> >> Robert >> >> >
