Re: [ANNOUNCE] Apache ZooKeeper 3.5.3-beta

2017-04-20 Thread Alexander Shraer 
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  wrote:

> On Thu, Apr 20, 2017 at 9:12 AM, Michael Han  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 
> 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 
> 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 
> > 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  >
> > > > 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  >
> > > > 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.
> >
>

Re: What is the role of Zookeeper and its external Integration dependencies

2017-04-20 Thread upendar devu 
Could you please respond to my query. Thanks

On Thu, Apr 13, 2017 at 2:46 PM, upendar devu 
wrote:

> Sorry looks like I missed to share my queries to dev team
>
> We are using zookeeper 3.4.6 version with integration of Apache Kafka ,
> Apache Storm and Zookeeper.
>
> I would like to understand the following things. Please help me to clarify.
>
> 1. What are Integration dependencies of Zookeeper ?
>Since we are using Kafka, Storm , so we need Zookeeper ? which external
> integration has dependencies
>
> 2. What is the actual role of zookeeper with the integration of Apache
> Kafka,Apache Storm.   Could you please provide a better use case to
> understand. sorry asking this question, I need to understand and am aware
> of this at least now from you.
>
> 3. We are planning to upgrade Zookeeper version to 3.4.10 due to CVE (
> CVE-2016-5017) mentioned with version 3.4.6 ;  Do we also need to upgrade
> depedency integration components like Apache Storm(*using 0.10.0*) and
> Apache Kafka (Using *0.8.1.1*) ? which version those should be upgraded
> to  ?
>
> On Thu, Apr 13, 2017 at 2:43 PM, upendar devu 
> wrote:
>
>> Including Dev Team to address my queries
>>
>> On Thu, Apr 13, 2017 at 2:39 PM, upendar devu 
>> wrote:
>>
>>> We are using zookeeper 3.4.6 version with integration of Apache Kafka ,
>>> Apache Storm and Zookeeper.
>>>
>>> I would like to understand the following things. Please help me to
>>> clarify.
>>>
>>> 1. What are Integration dependencies of Zookeeper ?
>>>Since we are using Kafka, Storm , so we need Zookeeper ? which
>>> external integration has dependencies
>>>
>>> 2. What is the actual role of zookeeper with the integration of Apache
>>> Kafka,Apache Storm.   Could you please provide a better use case to
>>> understand.
>>>
>>> 3. We are planning to upgrade Zookeeper version to 3.4.10 due to CVE (
>>> CVE-2016-5017) mentioned with version 3.4.6 ;  Do we also need to
>>> upgrade depedency integration components like Apache Storm(*using
>>> 0.10.0*) and Apache Kafka (Using *0.8.1.1*) ? which version those
>>> should be upgraded to  ?
>>>
>>>
>>> Thanks
>>> Upendar
>>>
>>
>>
>

Re: zookeeper node fails to communicate with Leader node

2017-04-20 Thread Michael Han 
The script should be simple enough to debug. Maybe try executing the
command yourself and see what happens? Could it be that JAVA_HOME was not
set correctly?


On Tue, Apr 18, 2017 at 1:24 PM, ravisinha0506 
wrote:

> I have a zookeeper cluster which includes 3 nodes. Zookeeper config is
> mentioned below. While restarting it shows a success message but it shows
> status as failure.
>
> zoo.cfg
>
> dataDir=/ngs/app//zookeeper-3.4.6/zookeeperdata/1
> clientPort=2181
> initLimit=5
> syncLimit=2
> server.1=pr2-ligerp-lapp27.:2888:3888
> server.2=pr2-ligerp-lapp28.:2889:3889
> server.3=pr2-ligerp-lapp29.:2890:3890
>
> sh zkServer.sh start
>
> JMX enabled by default
> Using config: /ngs/app/ligerp/solr/zookeeper-3.4.6/bin/../conf/zoo.cfg
> Starting zookeeper ... STARTED
> -bash-4.1$
> -bash-4.1$ cat zookeeper.out
> 2017-04-18 18:58:13,840 [myid:] - INFO  [main:QuorumPeerConfig@103] -
> Reading configuration from:
> /ngs/app/ligerp/solr/zookeeper-3.4.6/bin/../conf/zoo.cfg
> 2017-04-18 18:58:13,843 [myid:] - INFO  [main:QuorumPeerConfig@340] -
> Defaulting to majority quorums
> 2017-04-18 18:58:13,845 [myid:1] - INFO  [main:DatadirCleanupManager@78] -
> autopurge.snapRetainCount set to 3
> 2017-04-18 18:58:13,845 [myid:1] - INFO  [main:DatadirCleanupManager@79] -
> autopurge.purgeInterval set to 0
> 2017-04-18 18:58:13,846 [myid:1] - INFO  [main:DatadirCleanupManager@101]
> -
> Purge task is not scheduled.
> 2017-04-18 18:58:13,854 [myid:1] - INFO  [main:QuorumPeerMain@127] -
> Starting quorum peer
> 2017-04-18 18:58:13,861 [myid:1] - INFO  [main:NIOServerCnxnFactory@94] -
> binding to port 0.0.0.0/0.0.0.0:2181
> 2017-04-18 18:58:13,875 [myid:1] - INFO  [main:QuorumPeer@959] - tickTime
> set to 3000
> 2017-04-18 18:58:13,875 [myid:1] - INFO  [main:QuorumPeer@979] -
> minSessionTimeout set to -1
> 2017-04-18 18:58:13,875 [myid:1] - INFO  [main:QuorumPeer@990] -
> maxSessionTimeout set to -1
> 2017-04-18 18:58:13,875 [myid:1] - INFO  [main:QuorumPeer@1005] -
> initLimit
> set to 5
> 2017-04-18 18:58:13,884 [myid:1] - INFO  [main:FileSnap@83] - Reading
> snapshot
> /ngs/app/ligerp/solr/zookeeper-3.4.6/zookeeperdata/1/version-2/snapshot.
> 130032
> 2017-04-18 18:58:13,954 [myid:1] - INFO
> [Thread-1:QuorumCnxManager$Listener@504] - My election bind port:
> pr2-ligerp-lapp27./10.136.145.38:3888
> 2017-04-18 18:58:13,960 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumPeer@714] - LOOKING
> 2017-04-18 18:58:13,961 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:FastLeaderElection@815] - New
> election. My id =  1, proposed zxid=0x13024b
> 2017-04-18 18:58:13,962 [myid:1] - INFO
> [WorkerReceiver[myid=1]:FastLeaderElection@597] - Notification: 1 (message
> format version), 1 (n.leader), 0x13024b (n.zxid), 0x1 (n.round),
> LOOKING
> (n.state), 1 (n.sid), 0x13 (n.peerEpoch) LOOKING (my state)
> 2017-04-18 18:58:13,964 [myid:1] - INFO
> [WorkerSender[myid=1]:QuorumCnxManager@193] - Have smaller server
> identifier, so dropping the connection: (2, 1)
> 2017-04-18 18:58:13,964 [myid:1] - INFO
> [WorkerSender[myid=1]:QuorumCnxManager@193] - Have smaller server
> identifier, so dropping the connection: (3, 1)
> 2017-04-18 18:58:14,165 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller server identifier, so dropping the connection: (2, 1)
> 2017-04-18 18:58:14,166 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller server identifier, so dropping the connection: (3, 1)
> 2017-04-18 18:58:14,166 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:FastLeaderElection@849] -
> Notification time out: 400
> 2017-04-18 18:58:15,566 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller server identifier, so dropping the connection: (2, 1)
> 2017-04-18 18:58:15,567 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller server identifier, so dropping the connection: (3, 1)
> 2017-04-18 18:58:15,567 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:FastLeaderElection@849] -
> Notification time out: 800
> 2017-04-18 18:58:16,368 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller server identifier, so dropping the connection: (2, 1)
> 2017-04-18 18:58:16,368 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller server identifier, so dropping the connection: (3, 1)
> 2017-04-18 18:58:16,368 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:FastLeaderElection@849] -
> Notification time out: 1600
> 2017-04-18 18:58:17,969 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller server identifier, so dropping the connection: (2, 1)
> 2017-04-18 18:58:17,969 [myid:1] - INFO
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:QuorumCnxManager@193] - Have
> smaller

Re: [ANNOUNCE] Apache ZooKeeper 3.5.3-beta

2017-04-20 Thread Patrick Hunt 
On Thu, Apr 20, 2017 at 9:12 AM, Michael Han  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  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  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 
> 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 
> > > 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 
> > > 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.
>

Re: [ANNOUNCE] Apache ZooKeeper 3.5.3-beta

2017-04-20 Thread Michael Han 
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.

On Thu, Apr 20, 2017 at 6:53 AM, Ben Sherman  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  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  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 
> > 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 
> > 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.

Re: [ANNOUNCE] Apache ZooKeeper 3.5.3-beta

2017-04-20 Thread Ben Sherman 
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  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  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 
> 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 
> 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.
>