incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Wei Zhu <wz1...@yahoo.com>
Subject Re: Cluster not accepting insert while one node is down
Date Thu, 14 Feb 2013 20:35:36 GMT
>From the exception, looks like astyanax didn't even try to call Cassandra. My guess would
be astyanax is token aware, it detects the node is down and it doesn't even try. If you use
Hector, it might try to write since it's not token aware. But As Byran said, it eventually
will fail. I guess hinted hand off won't help since the write doesn't satisfy CL.ONE.


________________________________
 From: Bryan Talbot <btalbot@aeriagames.com>
To: user@cassandra.apache.org 
Sent: Thursday, February 14, 2013 8:30 AM
Subject: Re: Cluster not accepting insert while one node is down
 

Generally data isn't written to whatever node the client connects to.  In your case, a row
is written to one of the nodes based on the hash of the row key.  If that one replica node
is down, it won't matter which coordinator node you attempt a write with CL.ONE: the write
will fail.

If you want the write to succeed, you could do any one of: write with CL.ANY, increase RF
to 2+, write using a row key that hashes to an UP node.

-Bryan




On Thu, Feb 14, 2013 at 2:06 AM, Alain RODRIGUEZ <arodrime@gmail.com> wrote:

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...
>
>Alain
>
>
>
>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!Traian.
>>
>>
>>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.
>>>
>>>Alain
>>>
>>>
>>>
>>>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.
>>>>
>>>>Traian.
>>>>
>>>>
>>>>
>>>>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.
>>>>>
>>>>>Alain
>>>>>
>>>>>
>>>>>
>>>>>2013/2/13 Traian Fratean <traian.fratean@gmail.com>
>>>>>
>>>>>Hi,
>>>>>>
>>>>>>
>>>>>>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(10.60.15.67 - 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=10.60.15.66(10.60.15.66):9160, latency=2057(2057), attempts=1]UnavailableException()
>>>>>>com.netflix.astyanax.connectionpool.exceptions.TokenRangeOfflineException:
TokenRangeOfflineException: [host=10.60.15.66(10.60.15.66):9160, 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,
>>>>>>Traian.
>>>>>
>>>>
>>>
>>
>
Mime
View raw message