Hi
when you create a disk group you must create a pool if the disk group is virtual there can only be two virtual pools A and B
a virtual pool can contain many virtual disk groups but they are all considered as one storage space.
so if you are using virtual disk groups and don't want to use tiering you must create two pools one for the SAS drives and one for the SSD drives.
if you want to use linear disk groups you are not limited by number of pools but linear disk groups have other limitations
you can find information in HP MSA 2040 SMU Reference Guide
http://h20564.www2.hpe.com/hpsc/doc/public/display?docId=emr_na-c04220794
hope this help
Regards
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