issue from ZooKeeper 3.5.0

["Gao,Wei" <We...@Arcserve.com>]

Hi all,
  I encountered a problem which blocks my development of load balance using ZooKeeper 3.5.5.
   Actually, I have a ZooKeeper cluster which comprises of five zk servers. And the dynamic configuration file is as follows:

  server.1=zk1:2888:3888:participant;0.0.0.0:2181
  server.2=zk2:2888:3888:participant;0.0.0.0:2181
  server.3=zk3:2888:3888:participant;0.0.0.0:2181
  server.4=zk4:2888:3888:participant;0.0.0.0:2181
  server.5=zk5:2888:3888:participant;0.0.0.0:2181

  The zk cluster can work fine if every member works normally. However, if say two of them are suddenly down without previously being notified,
the dynamic configuration file shown above will not be synchronized dynamically, which leads to the zk cluster fail to work normally.
  As far as I am concerned, the dynamic configuration file should be modified to this if server 1 and server 5 are down suddenly as follows:
  server.2=zk2:2888:3888:participant;0.0.0.0:2181
  server.3=zk3:2888:3888:participant;0.0.0.0:2181
  server.4=zk4:2888:3888:participant;0.0.0.0:2181
But in this case, the dynamic configuration file will never change automatically unless you manually revise it.
  I think this is a very common case which may happen at any time. If so, how can we handle with it?
  Really look forward to hearing from you!
Thanks

Re: issue from ZooKeeper 3.5.0

[Enrico Olivelli <eo...@gmail.com>]

Hi Wei Gao,
The configuration file is expected to change only with an explicit
operation/client request.

You can have a fully working cluster of 5 servers with only 3 servers up
and running, you must not change the configuration files.

Can you tell more about your use case?

Enrico

Il mer 25 set 2019, 14:04 Gao,Wei <We...@arcserve.com> ha scritto:

> Hi all,
>   I encountered a problem which blocks my development of load balance
> using ZooKeeper 3.5.5.
>    Actually, I have a ZooKeeper cluster which comprises of five zk
> servers. And the dynamic configuration file is as follows:
>
>   server.1=zk1:2888:3888:participant;0.0.0.0:2181
>   server.2=zk2:2888:3888:participant;0.0.0.0:2181
>   server.3=zk3:2888:3888:participant;0.0.0.0:2181
>   server.4=zk4:2888:3888:participant;0.0.0.0:2181
>   server.5=zk5:2888:3888:participant;0.0.0.0:2181
>
>   The zk cluster can work fine if every member works normally. However, if
> say two of them are suddenly down without previously being notified,
> the dynamic configuration file shown above will not be synchronized
> dynamically, which leads to the zk cluster fail to work normally.
>   As far as I am concerned, the dynamic configuration file should be
> modified to this if server 1 and server 5 are down suddenly as follows:
>   server.2=zk2:2888:3888:participant;0.0.0.0:2181
>   server.3=zk3:2888:3888:participant;0.0.0.0:2181
>   server.4=zk4:2888:3888:participant;0.0.0.0:2181
> But in this case, the dynamic configuration file will never change
> automatically unless you manually revise it.
>   I think this is a very common case which may happen at any time. If so,
> how can we handle with it?
>   Really look forward to hearing from you!
> Thanks
>
>