John R Pierce wrote: > On 11/2/2017 9:21 AM, hw wrote: >> Richard Zimmerman wrote: >>> hw wrote: >>>> Next question: you want RAID, how much storage do you need? Will 4 or 8 3.5" drives be enough (DO NOT GET crappy 2.5" drives - they're *much* more expensive than the 3.5" drives, and >smaller disk space. For the price of a 1TB 2.5", I can get at least a 4TB WD Red. >>> >>> I will second Marks comments here. Yes, 2.5" drive enterprise drives have been an issue. +1 for the WD Red drives, so far 3.5" w/ 2tb and 4tb drives, ZERO issues. I've had good luck with HGST NAS drives too. Unfortunately, that will come to an end soon (With WD owning HGST). >> >> Most servers can fit only 2.5" disks these days. I keep wondering what >> everyone is doing about storage. > > > 2.5" SAS drives spinning at 10k and 15k RPM are the performance solution for online storage, like databases and so forth. also make more sense for large arrays of SSDs, as they don't even come in 3.5". With 2.5" you can pack more disks per U (24-25 2.5" per 2U face, vs 12 3.5" max per 2U)... more disks == more IOPS. That´s not for storage because it´s so expensive that you can only use it for the limited amounts of data that actually benefit from, or require, the advantage in performance. For this application, it makes perfectly sense. > 3.5" SATA drives spinning at 5400 and 7200 rpm are the choice for large capacity bulk 'nearline' storage which is typically sequentially written once Why would you write them only once? Where are you storing your data when you do that?