Hi there, We currently run an eight node cluster on Amazon EC2. This is perfect for our storage, but we want to add a couple of nodes (lets say 32) for processing a big task. We spin them up, run the jobs, and terminate the machines.
Sounds OK to me, however I'm aware of the fact that hadoop tries to replicate data blocks to other nodes in favor of balancing the cluster. I don't want this, as I will get under-replicated blocks when terminating the machines. We use juju for easy cluster administration. This implies that adding a new hadoop-slave runs both hdfs and hadoop (mapred). My main question is, is it possible to disable balancing the cluster, or just to disable the datanode service on the new nodes (meant for processing only)? Best regards, Robin Verlangen *Software engineer* * * W http://www.robinverlangen.nl E [email protected] Disclaimer: The information contained in this message and attachments is intended solely for the attention and use of the named addressee and may be confidential. If you are not the intended recipient, you are reminded that the information remains the property of the sender. You must not use, disclose, distribute, copy, print or rely on this e-mail. If you have received this message in error, please contact the sender immediately and irrevocably delete this message and any copies.
