Wow. Brutal, but effective.
On Thu, Sep 22, 2011 at 10:26 AM, Fournier, Camille F. < [email protected]> wrote: > We have a monitor process that runs 'stat' against the remote ZK and if it > returns leader, kills the process. > > -----Original Message----- > From: Damu R [mailto:[email protected]] > Sent: Thursday, September 22, 2011 12:47 PM > To: [email protected] > Subject: Re: zookeeper cluster spanning datacenters > > Hi Fourier, > > We spread our ZKs across 3 data centers and in fact, these data centers are > > split across global regions (2 or 4 in one region, one in a remote > region). > > To keep throughput up (and note that the throughput you have to worry > about > > is only write throughput), we always ensure that the master is in one of > the > > "local" data centers. > > > How can we make sure the master (leader?) is in the local datacenter? Is > there any way we can control the leader election? > > > > If you have the machines to test, I would recommend running zk-smoketest > ( > > https://github.com/phunt/zk-smoketest) on the proposed config. > > > This tool will be very useful to evaluate the setup. > > Thanks > Damu > > > > > C > > > > -----Original Message----- > > From: Damu R [mailto:[email protected]] > > Sent: Thursday, September 22, 2011 10:50 AM > > To: [email protected] > > Subject: zookeeper cluster spanning datacenters > > > > Hi, > > I would like to know the downsides of having a zookeeper cluster that > spans > > multiple datacenters. The requirement is a datacenter failure should not > > bring down the zookeeper cluster. From my understanding it is not > possible > > to have a hot/cold cluster kind of setup possible. So we are thinking of > > putting zk servers in 3 colos(1+1+1 or 2+2+3). One of the major drawback > I > > could think of is the throughput of the system affected by latency. The > > system does not require high throughput and can accept some latency. How > > much effect will the latency have on the throughput of the system? What > are > > the other downsides of spreading the cluster across datacenters? > > > > Regards > > Damu > > >
