On Thu, Jul 21, 2011 at 1:21 AM, Yves Langisch <[email protected]> wrote: > I just need a statement if it makes sense to use ephemeral storage for ZK at > all (in conjunction with Hbase if the answer depends on the use case)? > > Any help is appreciated. > > > On 19.07.2011 19:37, Yves Langisch wrote:
>> I plan to setup a HBase installation on EC2. As recommended I therefore >> want to setup a zookeeper ensemble with 3 nodes but I'm not sure what kind >> of storage I've to choose for the two zk directories (dataDir and >> dataLogDir). Do this two directories need to be on a persistent storage >> which survives a node crash? Or does an ephemeral storage device suffice >> since a failed node which is restarted is being synchronized with the other >> two nodes anyway? And what happens when I restart the whole zk ensemble with >> ephemeral storage which means there is no zk data available anymore after >> booting up? Any impact on the Hbase cluster? I don't think you want to use ephemeral storage given that HBase would lose information if the zk cluster was restarted. But really that's a better question for the hbase team, I don't know exactly how they are using ZK and the effects of such a loss on their application. Regards, Patrick
