The IBM Flex System x240 Compute Node is a high-performance Intel Xeon processor-based server that offers outstanding performance for virtualization. With two Intel Xeon E5-2600 processors, up to 24 DDR3 DIMM sockets and space for two 2.5-inch spinning drives or eight 1.8-inch solid-state drives, it packs quite a punch.
For internal storage, the x240 supports up to 2 TB with 1 TB 2.5-inch NL SAS HDDs, or up to 1.6 TB with eight 200 GB 1.8-inch SSDs . But what if your applications or virtual machines need more direct-attach storage than that? Enter the Storage Expansion Node, stage right!
The new Storage Expansion Node (SEN) is a locally attached storage node that is dedicated and directly attached to the compute node via a PCIe 3.0 x8 link. You can see it here attached to the x240 but the x220 also supports it. The SEN adds 12 hot-swap 2.5-inch drive bays. Using 1 TB drives, you can supply another 12 TB of internal storage to the server.
The drives are accessed by opening the handle on the front of the Storage Expansion Node and sliding out the drive tray. Opening the drive tray can be done while it is operational and with the appropriate RAID level employed, you can hot-swap a drive out in the event of a drive failure.
The SEN also includes an LSI SAS2208 6 Gbps RAID controller and connects to the compute node via its PCIe expansion connector. As a result, it looks to the system as just another PCI SAS controller with attached drives.
Drive modes supported are JBOD or RAID-0, 1, 5, 6, 10, 50, and 60. RAID 6 and 60 are optional via Feature on Demand upgrades but the other RAID levels are standard.
To learn more about the SEN, including architecture, a list of supported hard drives and upgrades, and more, see the Storage Expansion Node Product Guide from IBM Redbooks.
David Watts is an IBM Redbooks Project Leader. He writes books and papers on many areas related to IBM Flex System, IBM BladeCenter and IBM System x. Follow David on Twitter at @DavidAtRedbooks.