In general users are expected to run zookeeper cluster of 3 or 5 nodes. Zookeeper requires quorum of servers running which means at least ceil(n/2) servers need to be up. For 3 zookeeper nodes there needs to be atleast 2 zk nodes up at any time , i.e your cluster can function fine incase of 1 machine failure and incase of 5 there should be at least 3 nodes to be up and running. For more info on zookeeper you can look under here http://zookeeper.apache.org/doc/r3.4.6/ http://zookeeper.apache.org/doc/r3.4.6/zookeeperAdmin.html
-- Harsha On March 9, 2015 at 8:39:00 AM, Yuheng Du (yuheng.du.h...@gmail.com) wrote: Harsha, Thanks for reply. So what if the zookeeper cluster fails? Will the topics information be lost? What fault-tolerant mechanism does zookeeper offer? best, On Mon, Mar 9, 2015 at 11:36 AM, Harsha <ka...@harsha.io> wrote: Yuheng, kafka keeps cluster metadata in zookeeper along with topic metadata as well. You can use zookeeper-shell.sh or zkCli.sh to check zk nodes, /brokers/topics will give you the list of topics . -- Harsha On March 9, 2015 at 8:20:59 AM, Yuheng Du (yuheng.du.h...@gmail.com) wrote: I am wondering where does kafka cluster keep the topic metadata (name, partition, replication, etc)? How does a server recover the topic's metadata and messages after restart and what data will be lost? Thanks for anyone to answer my questions. best, Yuheng
