We have a cluster of 17 machines. Somewhere in the HBase documentation I read - usually we should divide by 2 & use an odd number. May be I mis-read. That's why I started Zookeeper on 9 machines. I guess, I don't understand the difference between Nodes & Instance. I expected ZKNodes to be 9. Please explain. Thanks a lot for your help.
On Tue, May 8, 2012 at 3:05 PM, Jordan Zimmerman <[email protected]>wrote: > You have 9 instances? That's a lot. Why so many? > > I believe the "Node" field in the stat is the number of ZKNodes, not > instances in the ensemble. That stat looks good. It means that that > instance is serving requests as a "follower" instance (one of the > instances will be the leader). > > -JZ > > On 5/8/12 2:54 PM, "Something Something" <[email protected]> wrote: > > >Hmm... > > > > > >Trying 127.0.0.1... > >Connected to localhost. > >Escape character is '^]'. > >stat > >Zookeeper version: 3.3.4-cdh3u3--1, built on 01/26/2012 20:09 GMT > >Clients: > > /127.0.0.1:42510[0](queued=0,recved=1,sent=0) > > > >Latency min/avg/max: 0/0/0 > >Received: 4 > >Sent: 3 > >Outstanding: 0 > >Zxid: 0x100000000 > >Mode: follower > >Node count: 11 > >Connection closed by foreign host. > > > > > >Not sure I understand this output. I have 9 nodes in the ensemble. > > > >On Tue, May 8, 2012 at 2:45 PM, Jordan Zimmerman > ><[email protected]>wrote: > > > >> Yes - they should. Keep in mind that the zoo.cfg, and the ID file must > >>be > >> correct and in agreement on each instance. You can do a stat on each > >> instance to see what state it's in: > >> > >> >telnet localhost 2181 > >> stat > >> > >> -JZ > >> > >> On 5/8/12 2:43 PM, "Something Something" <[email protected]> > >>wrote: > >> > >> >Thanks Jordan. Will definitely look at the cluster management tool. > >>In > >> >the mean time, am I correct with my assumption in #4? Once all of them > >> >are > >> >started they would automagically start talking to each other, right? > >> > > >> > > >> >On Tue, May 8, 2012 at 2:36 PM, Jordan Zimmerman > >> ><[email protected]>wrote: > >> > > >> >> Yes, you must start them all individually. ZooKeeper does not > >>currently > >> >> have any cluster-wide management tools built in. > >> >> > >> >> FYI - we've open sourced a cluster management tool for ZooKeeper. > >>Please > >> >> have a look: > >> >> > >> >> https://github.com/Netflix/exhibitor > >> >> > >> >> On 5/8/12 2:31 PM, "Something Something" <[email protected]> > >> >>wrote: > >> >> > >> >> >Hello, > >> >> > > >> >> >Trying to follow directions from here: > >> >> > > >> >> > >> >> > >> > >> > http://zookeeper.apache.org/doc/trunk/zookeeperAdmin.html#sc_zkMulitServe > >> >>r > >> >> >Setup > >> >> > > >> >> >to setup a cluster of zookeepers. > >> >> > > >> >> >Questions: > >> >> > > >> >> >1) If everything is setup correctly, do I have to go to each > >>machine > >> >>and > >> >> >start Zookeeper server in each of them individually? > >> >> >2) I was thinking if I start it on one master machine (well > >>there's no > >> >> >real master) then all zookeepers in the quorum would be started, but > >> >>this > >> >> >is not how it works correct? > >> >> >3) If I start individually, then I get messages saying the other > >> >> >zookeepers haven't started. Is that just a warning? > >> >> >4) When all of them are started, would they all be able to talk to > >> >>each > >> >> >other? > >> >> > > >> >> >Sorry for the dumb questions and thanks for the help. > >> >> > >> >> > >> > >> > >
