Hi, Our current cluster runs with 22 data nodes - each with 4TB . We should be installing new data nodes on this existing cluster , but each will have 8TB of storage capacity. I am wondering how will the namenode distribute the blocks, It is my understanding that Replica Placement policy is that data nodes are chosen at random, so an even distribution is expected , So eventually the smaller nodes will fill up while the larger nodes will reach 50% at which point the small nodes will become unusable. Am I correct? Is there any recommended practice in this case? would running a balancer periodically help?
