Got it . Thanks Alexander for the reply. Appreciate that.
> From: shra...@gmail.com > Date: Wed, 30 Sep 2015 23:16:12 -0700 > Subject: Re: Migrate Cluster > To: user@zookeeper.apache.org > > assuming you're using 3.4 release and doing reboots to add/remove servers, > option 2 doesn't seem safe. For example, > if you have servers A, B, C and you're adding D and E, note that its > possible that C isn't fully up to date since A and B can make progress > without C's acks (2 out of 3). When you reboot all servers its possible > that C forms a quorum with D and E (3 out of 5) and is elected leader. > Then, anything more recent A and B had will be lost. > > If I'm not mistaken option 1 shouldn't have this problem since any quorum > after each step always intersects any quorum before the step. > > If you're using 3.5 release you should be able to do the whole migration in > a single reconfiguration step. > > On Tue, Sep 29, 2015 at 11:31 AM, snair 123 <nair...@outlook.com> wrote: > > > Hello Experts > > I need to migrate an existing 3 node Zk ensemble to a different set of > > servers in a different networkSo servers A,B,C move to D,E,FWhat is the > > best way to do that without causing affecting the service > > This is is what we have been planning1. Add one node from the new network > > 2. Join and sync up 3. Remove one from the old network4. Do this for all > > the 3 nodes > > OR > > 1. Add 2 nodes in the new network2. Join and syncup3. Remove 2 nodes from > > the old network4. Add the 3rd node in the new network5. Make sure it is the > > leader ( a restart maybe ?)6. Remove the last remaining node from the old > > cluster > > The second option i would hope would ensure the leader stays in the > > network with most nodes and avoids problems due to network partitions ? > > > >