Is there still interest in this? Can we get some points down on electrons so that we all understand the issues?
While it is fairly simple to redirect the read/write to something other than the local system for a single node this will not solve the problem for tiered storage. Tiered storage will require that on read/write the primary key be assessed and determine if the read/write should be redirected. My reasoning for this statement is that in a cluster with a replication factor greater than 1 the node will store data for the keys that would be allocated to it in a cluster with a replication factor = 1, as well as some keys from nodes earlier in the ring. Even if we can get the primary keys for all the data we want to write to "cold storage" to map to a single node a replication factor > 1 means that data will also be placed in "normal storage" on subsequent nodes. To overcome this, we have to explore ways to route data to different storage based on the keys and that different storage may have to be available on _all_ the nodes. Have any of the partial solutions mentioned in this email chain (or others) solved this problem? Claude
