1. The coordinator still store system data and hints, but they should not store any user data since they are not part of ring. 2. We are using coordinator for thrift client. For cql based drivers, they needs to talk to nodes in the ring, so I think coordinator mode won't work for them.
-Dikang On Tue, May 9, 2017 at 2:01 PM, Anubhav Kale < anubhav.k...@microsoft.com.invalid> wrote: > Hello, > > > > With some inspiration from the Cassandra Summit talk from last year, we > are trying to setup a cluster with coordinator-only nodes. We setup > join_ring=false in env.sh, disabled auth in YAML and the nodes are able to > start just fine. However, we’re running into a few problems > > > > 1] The nodes marked with join_ring=false continue to store data. Why ? > > 2] We tried Python driver’s whitelistedpolicy. But we notice message like > below, so we are not able to send queries to all nodes marked as > coordinators. We also changed the Scala driver to support whitelisting, but > see the same thing. What are we missing ? > > 3] Is there any way to concretely tell that only coordinator nodes are > getting requests from clients ? We don’t have OpsCenter. > > > > Thanks ! > > > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: [control connection] > Removing host not found in peers metadata: <Host: 10.80.10.128> > > 2017-05-09 20:45:25,060 [INFO] cassandra.cluster: Cassandra host > 10.80.10.128 removed > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: Removing host > 10.80.10.128 > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: [control connection] > Removing host not found in peers metadata: <Host: 10.80.10.127> > > 2017-05-09 20:45:25,060 [INFO] cassandra.cluster: Cassandra host > 10.80.10.127 removed > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: Removing host > 10.80.10.127 > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: [control connection] > Removing host not found in peers metadata: <Host: 10.80.10.129> > > 2017-05-09 20:45:25,060 [INFO] cassandra.cluster: Cassandra host > 10.80.10.129 removed > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: Removing host > 10.80.10.129 > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: [control connection] > Finished fetching ring info > > 2017-05-09 20:45:25,060 [DEBUG] cassandra.cluster: [control connection] > Rebuilding token map due to topology changes > > 2017-05-09 20:45:25,081 [DEBUG] cassandra.metadata: user functions table > not found > > 2017-05-09 20:45:25,081 [DEBUG] cassandra.metadata: user aggregates table > not found > > 2017-05-09 20:45:25,098 [DEBUG] cassandra.cluster: Control connection > created > > 2017-05-09 20:45:25,099 [DEBUG] cassandra.pool: Initializing connection > for host 10.80.10.125 > > 2017-05-09 20:45:25,099 [DEBUG] cassandra.pool: Initializing connection > for host 10.80.10.126 > > > -- Dikang
