Substituting the SAS drive will necessarily degrade the performance of the SSD array, but also protect the integrity of the data stored on the SSD. When the failed SSD is replaced, the SAS replacement dumps all of its content to the new SSD and resumes its position as a hot spare, so the SSD array will once again be up to full speed. Given the price and higher reliability of the SSD, this scenario is acceptable, but it's wise to keep a cold spare SSD on hand.
The EqualLogic PS6010XVS represents yet another impressive product from Dell. The only downside is the relatively small capacity of the solution. Of the raw 4.4TB capacity, you'll see 500GB of SSD storage and roughly 2TB in SAS storage available for general use. The decision to go with the 450GB SAS drives was made to keep the ratio of SAS to SSD storage around 4:1, helping to maximize the performance enhancements of the SSD. That positions the Dell PS6010XVS not as a general-purpose array, but one that would be best utilized for highly transactional workloads and heavily loaded virtual servers. As with all EqualLogic arrays, the PS6010XVS will fall right into place alongside other EqualLogic units and can be managed from within the same group.
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