On 08/30/2015 12:02 PM, Mike Mohr wrote: > In my experience the mass market HBAs and RAID cards typically do support > only 8 or 16 drives. For the internal variety in a standard rack-mount > server you'll usually see either 2 or 4 iPass cables (each of which support > 4 drives) connected to the backplane. The marketing material you've > referenced has a white lie in it: supporting more than 16 drives on a > single card is very likely only possible with an additional SAS expander > board. I believe Supermicro does sell some pre-configured systems with ok, then i should give a little detail : the purpose was to have an 1U server as a head of a JBOD chassis that have 2 SAS backplanes. The connection would be a simple SAS cascade to the backplanes. > such hardware, but expect the throughput to fall through the floor if you > use such hardware. why? what is the difference between the silicon from a HBA card and the same silicon on motherboard? The reason of my post is also to understand why is/is not possible.. Thank you, Adrian > Bottom line: the Supermicro application engineer knows what he's talking > about. > > On Sun, Aug 30, 2015 at 1:13 AM, Adrian Sevcenco <Adrian.Sevcenco@xxxxxxx> > wrote: > >> Hi guys! Unfortunately there is no offtopic list but the subject >> is somehow related to centos as the OS is/will be centos :) >> So, under this thin cover i ask : >> Is it possible that for a SAS controler like LSI 3008 that in specs >> says that : "This high-performance I/O controller supports T-10 >> data protection model and optical support, PCIe hot plugging, >> and up to 1,000 connected devices" in a vendor implementation >> (motherboard integrated) to support only 8 (or 16) devices? >> The technical support from the OEM told me that "the onboard >> SAS controller maximum amount of supported harddrives is 16pcs" >> and "if you are planning on using more than 16 drives then you >> have to use a PCI-E card based SAS controller with external ports >> (which Supermicro does not sell)" >> and both statements sound insane to me! >> First, because the specs for 3008 says something else and i dont know >> how one can artificially reduce the number of supported hdds >> (beside the firmware - but why would one do that?) and >> the second statement is just hogwash as the externl/internal status of >> the ports have nothing to do with the sas cascading and the number of >> devices supported!! (and of course is really cheap to convert an internal >> port to an external port with a bracket) >> So, i ask you guys that have more knowledge and expertise: was this >> Senior Application Engineer that answered me a total incompetent? >> >> Thank you! >> Adrian >> >> >> _______________________________________________ >> CentOS mailing list >> CentOS@xxxxxxxxxx >> https://lists.centos.org/mailman/listinfo/centos >> >> > _______________________________________________ > CentOS mailing list > CentOS@xxxxxxxxxx > https://lists.centos.org/mailman/listinfo/centos >
_______________________________________________ CentOS mailing list CentOS@xxxxxxxxxx https://lists.centos.org/mailman/listinfo/centos
