zookeeper-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Guillermo Vega-Toro" <gvega...@us.ibm.com>
Subject How to add nodes to a Zookeeper 3.5.3-beta ensemble with reconfigEnabled=false
Date Wed, 21 Jun 2017 18:33:52 GMT

I have a 3-node Zookeeper 3.5.3-beta ensemble. This was initially created 
by un-taring the Zookeeper tarball into 3 machines, editing the zoo.cfg 
file with the 3 server entries, and starting the servers. The ensemble 
started, and a zoo.cfg.dynamic.100000000 file was created with the 
server.x lines in all servers.

Now, I want to add 2 more nodes to grow to a 5-node ensemble. In Zookeeper 
3.4.6, I would install the two new nodes, update the zoo.cfg files on all 
servers to add the new nodes, and restart the servers one by one. But in 
version 3.5.3-beta, this is not possible - any changes made to 
zoo.cfg.dynamic.100000000 are ignored, even if reconfiguration is 
disabled. If the dynamic config file is modified to add new servers and 
the server is restarted, the dynamic config file gets overwritten with the 
old 3-node configuration when the server starts.

So, it looks like in Zookeeper 3.5.x, the way to add nodes is to use the 
new reconfig command on the CLI. But if the reconfiguration feature is 
disabled for security reasons (as it is in 3.5.3-beta by default), then 
adding nodes "the old way" by editing the config file and restarting the 
servers is not possible either. Does this mean that in Zookeeper 
3.5.3-beta, in order to grow the ensemble, it is necessary to enable 
reconfiguration (by setting reconfigEnabled=true in zoo.cfg and restarting 
all servers), then running the CLI to add the new nodes? Then after the 
new nodes are added, edit zoo.cfg to disable reconfiguration on all 
servers, and restart all servers again?


  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message