Hi,

We have an FS7300 with the control enclosure populated with FCM3 modules configured as a single array in a pool.

We are planning to add an expansion enclosure with additional FCMs and the array made from these would be added to the existing pool.

I am assuming that the external FCMs still will be considered tie0_flash. As there would be difference in throughput between the internal NVMe-attached vs the external SAS-attached FCMs we would like to override the tier for the new SAS array. Will the chmdisk or addmdisk commands allow us to manually change the tier for the new array? The documentation is not clear on this point.

Hi Zaki,

expansion enclosures does not support FCM's. You can add another control enclosure with FCM's. 

Hi Nezih,

Many thanks for clarfying on that point. (It's always a joy to read replies from you and Evelyn.)

If we go with the expansion enclosure, the array from the SAS-attached SSDs will be designated as tier1_flash and EasyTier will be active between the tier0 and tier1 arrays in the pool. I hope I am not missing anything here.

Hi Zaki,

Yes, you are right. But I prefer to use it like fcm volumes and tier1 volumes.