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Can you tolerate an outage = if a JBOD I/O controller fails? If so, then you don't need dual-port. = But server crashes are more common than JBOD I/O controller failures. = So you should worry more about that. >=20 > Thank you Alan. > Of course you're right, JBOD IO controller is not the first outage = cause, and disks themselves are more prone to fail... >=20 > I even wonder whether or not dual path is actively used for HDDs, as = dual-port ones are rather hard to find... > Not sure then it's really worth it... >=20 > Of course feel free if I'm wrong / I missed something / one actively = uses it and has some experience / references to share ! >=20 > Thank you again, >=20 > Ben >=20 > Sure, dual paths are actively used. They work well with gmultipath, = which is how I use them. And AFAIK all SAS drives are dual-ported. = Western Digital describes their drives as "dual port" on this site: > = https://www.westerndigital.com/products/data-center-platforms/ultrastar-sa= s-series-ssd = You're right, SAS SSDs are dual-port. However, their SAS HDDs are not advertised as such : = https://www.westerndigital.com/products/data-center-platforms/ultrastar-dc= -hc600-series-hdd = https://www.westerndigital.com/products/data-center-platforms/ultrastar-dc= -hc500-series-hdd So I wonder. Ben