As David said, once a shelf is added to an array it is married. However if you needed to upgrade the shelf you can remove it after you have migrated data off the array. The good news is with our 2.0 code you can do this this process fairly easily with no downtime by doing the following:
- Bring a second array and shelf with enough storage into the 2.0 cluster.
- Migrate the storage pool from the original array to the newly added array.
- Evacuate the original CS210 and shelf
- Work with support to remove the current shelf and add the new shelf
- Import the original array into the 2.0 cluster
- Migrate the storage pool back to the original array
- Evacuate the temporary array.
At this point you will be back on the original array with the new shelf. All of this can be done with zero downtime. If you need a loaner array to preform this work, work with your account team. Your SE can help with this process as well.