I will let commiters or anyone that has knowledge on Cassandra internal answer this.

From what I understand, you should be able to insert data on any up node with your configuration...


2013/2/14 Traian Fratean <traian.fratean@gmail.com>
You're right as regarding data availability on that node. And my config, being the default one, is not suited for a cluster.
What I don't get is that my 67 node was down and I was trying to insert in 66 node, as can be seen from the stacktrace. Long story short: when node 67 was down I could not insert into any machine in the cluster. Not what I was expecting.

Thank you for the reply!

2013/2/14 Alain RODRIGUEZ <arodrime@gmail.com>
Hi Traian,

There is your problem. You are using RF=1, meaning that each node is responsible for its range, and nothing more. So when a node goes down, do the math, you just can't read 1/5 of your data.

This is very cool for performances since each node owns its own part of the data and any write or read need to reach only one node, but it removes the SPOF, which is a main point of using C*. So you have poor availability and poor consistency.

An usual configuration with 5 nodes would be RF=3 and both CL (R&W) = QUORUM.

This will replicate your data to 2 nodes + the natural endpoints (total of 3/5 nodes owning any data) and any read or write would need to reach at least 2 nodes before being considered as being successful ensuring a strong consistency.

This configuration allow you to shut down a node (crash or configuration update/rolling restart) without degrading the service (at least allowing you to reach any data) but at cost of more data on each node.


2013/2/14 Traian Fratean <traian.fratean@gmail.com>
I am using defaults for both RF and CL. As the keyspace was created using cassandra-cli the default RF should be 1 as I get it from below:

[default@TestSpace] describe;
Keyspace: TestSpace:
  Replication Strategy: org.apache.cassandra.locator.NetworkTopologyStrategy
  Durable Writes: true
    Options: [datacenter1:1]

As for the CL it the Astyanax default, which is 1 for both reads and writes.


2013/2/13 Alain RODRIGUEZ <arodrime@gmail.com>
We probably need more info like the RF of your cluster and CL of your reads and writes. Maybe could you also tell us if you use vnodes or not.

I heard that Astyanax was not running very smoothly on 1.2.0, but a bit better on 1.2.1. Yet, Netflix didn't release a version of Astyanax for C*1.2.


2013/2/13 Traian Fratean <traian.fratean@gmail.com>

I have a cluster of 5 nodes running Cassandra 1.2.0 . I have a Java client with Astyanax 1.56.21.
When a node( - diiferent from the one in the stacktrace below) went down I get TokenRandeOfflineException and no other data gets inserted into any other node from the cluster.

Am I having a configuration issue or this is supposed to happen?

com.netflix.astyanax.connectionpool.impl.CountingConnectionPoolMonitor.trackError(CountingConnectionPoolMonitor.java:81) - com.netflix.astyanax.connectionpool.exceptions.TokenRangeOfflineException: TokenRangeOfflineException: [host=, latency=2057(2057), attempts=1]UnavailableException()
com.netflix.astyanax.connectionpool.exceptions.TokenRangeOfflineException: TokenRangeOfflineException: [host=, latency=2057(2057), attempts=1]UnavailableException()
at com.netflix.astyanax.thrift.ThriftConverter.ToConnectionPoolException(ThriftConverter.java:165)
at com.netflix.astyanax.thrift.AbstractOperationImpl.execute(AbstractOperationImpl.java:60)
at com.netflix.astyanax.thrift.AbstractOperationImpl.execute(AbstractOperationImpl.java:27)
at com.netflix.astyanax.thrift.ThriftSyncConnectionFactoryImpl$1.execute(ThriftSyncConnectionFactoryImpl.java:140)
at com.netflix.astyanax.connectionpool.impl.AbstractExecuteWithFailoverImpl.tryOperation(AbstractExecuteWithFailoverImpl.java:69)
at com.netflix.astyanax.connectionpool.impl.AbstractHostPartitionConnectionPool.executeWithFailover(AbstractHostPartitionConnectionPool.java:255)

Thank you,