LSI 9260-4i connects up to 128 SATA/SAS devices?

[mxnerd]

According to the spec on the web, this LSI (now Avago) MegaRAID controller can connect up to 128 devices.

But how? It has only one 1 Mini-SAS SFF8087 connector, which can connect only 4 drives.

However it supports RAID 50 & 60, which require 6 drives and 8 drives separately, how is this achieved?

http://www.lsi.com/products/raid-controllers/pages/megaraid-sas-9260-4i.aspx#tab/tab2

Can someone explain it to me? Thanks.

 

[386DX]

It's achieved by using expander cards or if you buy a storage rack (example 24 bay Norco) they typically have expanders built into the backplane. The expander cards just feeds the data to the LSI card, all the RAID, parity calculations done by the 9260 card.

 

[w0ss]

a port expander is used to connect to extra drives. Think of it like a network switch but for SATA/SAS.

 

[mxnerd]

I see, thanks guys!