A while ago, on my first cluster, I decided to do an upgrade by adding nodes running 1.2 to an existing cluster running version 1.1. This was a bad decision, and at that point I decided to always play it safe and always stick to a single version, and never bootstrap in a node running different version to a cluster.
I would do this even when it's a trivial upgrade, or a single commit is different only touching a few lines of code. Why? I do this because in my opinion it's better to have a single way of doing things. Getting in the routine of doing minor upgrades by following Sean's upgrade checklist will always work. It's the supported, correct way of doing things, and if you decide to always follow the same checklist, the possibility of doing things wrong when there is an incompatibility decreases. Think of it as practice. The only time you should even consider mixed version bootstrap upgrades is if you know enough to not have to ask the list. Even then, I go back to my previous point about practice. No point in practicing the less safe version of things. My 2 cents. Jon On Wed, Feb 12, 2020 at 11:02 AM Sergio <lapostadiser...@gmail.com> wrote: > Thanks for your reply! > > So unless the sstable format has not been changed I can avoid to do that. > > Correct? > > Best, > > Sergio > > On Wed, Feb 12, 2020, 10:58 AM Durity, Sean R <sean_r_dur...@homedepot.com> > wrote: > >> Check the readme.txt for any upgrade notes, but the basic procedure is to: >> >> - Verify that nodetool upgradesstables has completed successfully on >> all nodes from any previous upgrade >> - Turn off repairs and any other streaming operations (add/remove >> nodes) >> - Stop an un-upgraded node (seeds first, preferably) >> - Install new binaries and configs on the down node >> - Restart that node and make sure it comes up clean (it will function >> normally in the cluster – even with mixed versions) >> - Repeat for all nodes >> - Run upgradesstables on each node (as many at a time as your load >> will allow). Minor upgrades usually don’t require this step (only if the >> sstable format has changed), but it is good to check. >> - NOTE: in most cases applications can keep running and will not >> notice much impact – unless the cluster is overloaded and a single node >> down causes impact. >> >> >> >> >> >> >> >> Sean Durity – Staff Systems Engineer, Cassandra >> >> >> >> *From:* Sergio <lapostadiser...@gmail.com> >> *Sent:* Wednesday, February 12, 2020 11:36 AM >> *To:* user@cassandra.apache.org >> *Subject:* [EXTERNAL] Cassandra 3.11.X upgrades >> >> >> >> Hi guys! >> >> How do you usually upgrade your cluster for minor version upgrades? >> >> I tried to add a node with 3.11.5 version to a test cluster with 3.11.4 >> nodes. >> >> Is there any restriction? >> >> Best, >> >> Sergio >> >> ------------------------------ >> >> The information in this Internet Email is confidential and may be legally >> privileged. It is intended solely for the addressee. Access to this Email >> by anyone else is unauthorized. If you are not the intended recipient, any >> disclosure, copying, distribution or any action taken or omitted to be >> taken in reliance on it, is prohibited and may be unlawful. When addressed >> to our clients any opinions or advice contained in this Email are subject >> to the terms and conditions expressed in any applicable governing The Home >> Depot terms of business or client engagement letter. The Home Depot >> disclaims all responsibility and liability for the accuracy and content of >> this attachment and for any damages or losses arising from any >> inaccuracies, errors, viruses, e.g., worms, trojan horses, etc., or other >> items of a destructive nature, which may be contained in this attachment >> and shall not be liable for direct, indirect, consequential or special >> damages in connection with this e-mail message or its attachment. >> >
