The issue Patrick was referring to is described here: https://zookeeper.apache.org/doc/trunk/zookeeperReconfig.html#ch_reconfig_upgrade
On Thu, Apr 20, 2017 at 9:22 AM, Patrick Hunt <ph...@apache.org> wrote: > On Thu, Apr 20, 2017 at 9:12 AM, Michael Han <h...@cloudera.com> wrote: > > > Just to clarify, 4LW feature is not removed in latest releases (3.4.10 > and > > 3.5.3-beta). The feature is still there, it's just disabled by default. > You > > can enable the feature if you need it (details in the admin documents). > > Because of the compatibility guarantees provided by ZooKeeper, we > wouldn't > > just remove a feature lightly. > > > > > 3.5 also adds json support through jetty/http, a significant improvement > over 4lw. > > Patrick > > > > On Thu, Apr 20, 2017 at 6:53 AM, Ben Sherman <bensher...@gmail.com> > wrote: > > > > > Thanks for the 4lw warning - I was going to upgrade to 3.4.10 today but > > > didn't expect features to be removed. It's a shame they are going > away, > > > human readable output from a one line script was a nice feature to have > > by > > > default. > > > > > > On Wed, Apr 19, 2017 at 6:02 PM, Michael Han <h...@cloudera.com> > wrote: > > > > > > > >> pitfalls coming from 3.4.9 (or .10) to the 3.5.x release? > > > > If coming from 3.4.9, one note is all four letter words except srvr > are > > > > disabled by default in 3.5.3 so your devops tool if they depend on > 4lw > > > will > > > > stop working (one user already reports this on jira), which is > > expected. > > > In > > > > this case you can either update configuration to enable the subset of > > 4lw > > > > you need, or use modern monitoring primitives provided by ZK (JMX / > > Jetty > > > > admin server). If coming from 3.4.10 then it's fine, since 3.4.10 > made > > > same > > > > change to 4lw (disable by default). > > > > > > > > >> make a change to 3.4.x (x>0) in order to maintain backward compat > > > with a > > > > change that we made to 3.5. > > > > Not sure if it's ZOOKEEPER-1633. Basically rolling upgrade would not > > work > > > > from 3.4.x to 3.5.y if x < 6. > > > > > > > > On Wed, Apr 19, 2017 at 5:16 PM, Patrick Hunt <ph...@apache.org> > > wrote: > > > > > > > > > I remember we had to make a change to 3.4.x (x>0) in order to > > maintain > > > > > backward compat with a change that we made to 3.5. I searched but I > > > can't > > > > > remember the specific jira or the specific release, it was some > time > > > ago. > > > > > The issue would be that if you try and do a rolling upgrade from > > > 3.4.x-1 > > > > to > > > > > 3.5.y it had the potential to fail. Perhaps one of the other > > community > > > > > folks will remember. Other than that I'm not aware of anything. The > > on > > > > disk > > > > > formats are the same and the communication protocols should be b/w > > > > compat. > > > > > I tried running 3.4 client against 3.5.3 during the last release > and > > it > > > > > worked ok for me. Not sure if anyone has been testing at the quorum > > > > level. > > > > > > > > > > If anyone does find something (or tests and finds it works) please > > let > > > us > > > > > know so that we can document it. > > > > > > > > > > Patrick > > > > > > > > > > On Wed, Apr 19, 2017 at 4:14 PM, Ben Sherman <bensher...@gmail.com > > > > > > wrote: > > > > > > > > > > > Great news, are there any docs written yet or any known pitfalls > > > coming > > > > > > from 3.4.9 (or .10) to the 3.5.x release? > > > > > > > > > > > > On Mon, Apr 17, 2017 at 10:48 AM, Michael Han <h...@cloudera.com > > > > > > wrote: > > > > > > > > > > > > > The Apache ZooKeeper team is proud to announce Apache ZooKeeper > > > > version > > > > > > > *3.5.3-beta*. > > > > > > > > > > > > > > ZooKeeper is a high-performance coordination service for > > > distributed > > > > > > > applications. It exposes common services - such as naming, > > > > > > > configuration management, synchronization, and group services - > > in > > > a > > > > > > > simple interface so you don't have to write them from scratch. > > You > > > > can > > > > > > > use it off-the-shelf to implement consensus, group management, > > > leader > > > > > > > election, and presence protocols. And you can build on it for > > your > > > > > > > own, specific needs. > > > > > > > > > > > > > > For ZooKeeper release details and downloads, visit: > > > > > > > https://zookeeper.apache.org/releases.html > > > > > > > > > > > > > > ZooKeeper 3.5.3-beta Release Notes are at: > > > > > > > https://zookeeper.apache.org/doc/r3.5.3-beta/releasenotes.html > > > > > > > > > > > > > > We would like to thank the contributors that made the release > > > > possible. > > > > > > > > > > > > > > Regards, > > > > > > > > > > > > > > The ZooKeeper Team > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > Cheers > > > > Michael. > > > > > > > > > > > > > > > -- > > Cheers > > Michael. > > >
