EU WTB: 60+ bay JBOD

[Rand__]

That was the original idea, yes, to build a HA capable ZFS Filer

 

[ari2asem]

Regarding speed - I have annoyed the WD support a bit and got the following results after a bit back and forth


Q:
I know the JBOD supports SAS3 harddrives, and it has QSFP connectors.
Can you please confirm that the QSFP port outputs SAS3? I assume 4 lanes per EOM?
Assuming that is the case, can i connect both EOMs to a single host to increase the bandwith? Or can this only be used for multipathing.

A: Regarding SAS3/QSFP query:
1) The frontend ports of each ESM are support QSFP+ - Refer user guide for supported QSFP+ cables.
2) Yes, Each ports internally has 4 lanes.
3) If a single Host is connected to the frontend port of both of the ESMs, then this configuration will give you both - Increase bandwidth and Multipathing capabilities.

single host? is that 1 hba with 4 external ports? and then the bandwidth is limited by pcie-3 speed?

Q:

Regarding the QSFP+ port - just to be sure, the 4 lanes carry SAS3, right?
So the maximum bandwith I can get when connecting the box to two servers is 4x12Gb/s (6 GB/s) limited by the use of a single port on a HBA/Raid Controller (4 lanes of PCIe3 = 4x985MB/s=3940MB/s) - this is just to confirm the maximum theoretical bandwith

A: QSFP+ port:
1) Yes, 4 lanes carry SAS3.
2) Yes, the maximum bandwidth that you can get with 4 lanes of PCIe3 = 4x985MB/s=3940MB/s theoretically.

Which tells me I need to get a PCIe4 HBA for these

so you can connect all 4 ports of qsfp to a sinlge hab with 4 ports?
but which factor is then limiting the bandwidth?

 

[Rand__]

No, only 2 of the 4 are usable for host connection, others are for daisy chaining.

 

[ari2asem]

No, only 2 of the 4 are usable for host connection, others are for daisy chaining.

so, for my clearification....1 qsfp port is 4x sas3 speed, meaning 1 qsfp port is at maximum 48gbps (4x sas3=12gbps)? do i understand this right?

next question....connecting 2 IN qsfp ports (from hgst-unit, from 2 io-modules) to 2 ports of 1 hba will give me aggregated (higher bandwidth) link if my hba-card support that?

 

[Rand__]

Yes, thats how i understood it.

 

[ari2asem]

i guess that my hgst gen1 unit has firmware version 0210. i see that with LSI storage managment software (megaraid storage manager, msm) under ENCLOSURE, text is something REVISION NUMBER .

my unit is accepting seagate sata600 hdd (tried 3tb and 10tb), connected with one qsfp+ -> sff-8088 cable to Lsi 9201-16e card (with card firmware 19)

a question to all owners of hgst units:

can you post your firmware version and whether it is accepting seagate drives or not. plz, also note gen-number.
thanks in advance