Thanks.
It worked when I changed as you suggested to: create keyspace ks1 with
strategy_options = [{DC1:1, DC2:1}] and
placement_strategy='org.apache.cassandra.locator.NetworkTopologyStrategy';Something that I am observing: The replicas are always put in the first node on the other DC. (So if there are 2 nodes in each DC, replica of both nodes goes to the first node in the other DC. And vice-versa) This would make the first node in each DC a hotspot. Am I doing something wrong ? If not, any way to avoid this ? On Thu, Mar 3, 2011 at 3:41 PM, Jonathan Ellis <jbel...@gmail.com> wrote: > you need to specify per-DC replicas w/ NTS in strategy_options, > instead of using replication_factor > > On Thu, Mar 3, 2011 at 1:52 PM, A J <s5a...@gmail.com> wrote: >> using latest cassandra (0.7.2). I want to try out Network Topology Strategy. >> >> Following is related setting in cassandra.yaml >> endpoint_snitch: org.apache.cassandra.locator.PropertyFileSnitch >> >> I have four nodes. Set them accordingly in >> ./conf/cassandra-topology.properties: >> 10.252.219.224=DC2:RAC1 >> 10.252.10.64=DC2:RAC1 >> 10.252.11.32=DC1:RAC1 >> 10.220.103.98=DC1:RAC1 >> >> >> I create a ks as: >> create keyspace ks1 with replication_factor=1 and >> placement_strategy='org.apache.cassandra.locator.NetworkTopologyStrategy'; >> >> When I try to insert, get the following error: >> set cf1['A']['c1']='xyz'; >> ERROR 19:21:58,081 Internal error processing insert >> java.lang.AssertionError: invalid response count 1 for replication factor 0 >> >> >> Please suggest what could be going on ? cassandra-topology.properties >> has two DCs. Why am I still getting the error ? >> >> Thanks for any suggestions. >> > > > > -- > Jonathan Ellis > Project Chair, Apache Cassandra > co-founder of DataStax, the source for professional Cassandra support > http://www.datastax.com >
