Thanks, This clarifies the situation.
Regards, Juha On Fri, Sep 3, 2021 at 11:53 AM Till Rohrmann <[email protected]> wrote: > For patch versions the Flink community is very careful not to introduce > breaking changes. Hence, for patch releases it should be possible to > upgrade via failover. However, I don't think that this is properly guarded > by tests at the moment and also no official guarantee we are giving. > > Cheers, > Till > > On Fri, Sep 3, 2021 at 9:40 AM Juha Mynttinen > <[email protected]> wrote: > > > OK, thanks, > > > > I see, this savepointing and creating a new cluster is the documented [1] > > way of upgrading Flink version. However, I think at least for some > version > > upgrades it has been fine to just switch the code to the new version. I > > might be wrong. > > > > What about patch versions like 1.13.X? The doc says "the general way of > > upgrading Flink across version". Can there be breaking changes in patch > > versions too? > > > > Regards, > > Juha > > > > [1] > > > > > https://ci.apache.org/projects/flink/flink-docs-master/docs/ops/upgrading/#upgrading-the-flink-framework-version > > > > > > > > On Fri, Sep 3, 2021 at 9:49 AM Till Rohrmann <[email protected]> > wrote: > > > > > Hi Juha, > > > > > > Flink does not give backwards compatibility wrt to its internal data > > > structures. The recommended way is to stop the jobs with a savepoint > and > > > then resume these jobs on the new Flink cluster. Failing over the > > processes > > > with a new version is not guaranteed to work atm. I hope this answers > > your > > > question. > > > > > > Cheers, > > > Till > > > > > > On Fri, Sep 3, 2021 at 7:35 AM Juha Mynttinen > > > <[email protected]> wrote: > > > > > > > Hello, > > > > > > > > I noticed there's a change [1] coming up in Flink 1.14.0 in the > > ZooKeeper > > > > tree structure ZooKeeper HA services maintains. > > > > > > > > I didn't spot any migration logic from the old (< 1.14.0) structure > to > > > the > > > > new. Did I miss something? > > > > > > > > If you have a Flink cluster running with 1.13.X and let's say add a > > > > JobManage with 1.14.0 and terminate the original so that the new one > > > > becomes the leader, how's the new one going to understand the data in > > > > ZooKeeper? There are naturally more cases where the same > compatibility > > > > issue should be handled, this example should illustrate the issue. > > > > > > > > Regards, > > > > Juha > > > > > > > > [1] https://issues.apache.org/jira/browse/FLINK-22636 > > > > > > > > > > > > > -- > > Regards, > > Juha > >
