HP BladeSystem c-Class architecture Technology brief, 4th edition

Figure 9: Connection of half-height server blades to the interconnect bays in the BladeSystem c3000 enclosure

For more information about connections, review the enclosure quick start guides at

http://h18004.www1.hp.com/products/blades/components/c-class-tech-installing.html.

To provide these connections, c-Class architecture must supply a mechanism to match the mezzanine

cards on the server blades to the interconnect modules. The electronic keying mechanism in the

Onboard Administrator helps your system administrators correct potential fabric mismatch conditions

when they configure each enclosure. Before any server blade or interconnect module can power up,

the Onboard Administrator, assisted by an iLO processor on each server blade, queries the

mezzanine cards and interconnect modules to see if they are compatible. If the Onboard

Administrator detects a configuration problem, it gives a warning and provides information to correct

the problem.

Blade-to-blade connectivity

The NonStop signal midplane allows you to use more modular components than previous generations

of blade systems. We can develop components in the blade form factor and connect them across the

NonStop signal midplane—front-to-back or side-to-side. The architecture supports front-to-back

modularity by connecting mezzanine cards in the server blades at the front of the enclosure to the

matching interconnect modules in the rear of the enclosure.

There are four dedicated lanes between each side-by-side pair (odd/even) of device bays. This lets

you connect optional storage or I/O devices to a server blade through the midplane. The Onboard

Administrator disables these side-to-side links when they are unusable, such as when two server

blades reside in adjacent device bays.

Some examples of storage and I/O device options using the dedicated links to a server blade

include:

• StorageWorks SB40c Storage Blade that consist of a RAID controller and additional drives

• StorageWorks Ultrium Tape Blades that hold LTO-2, LTO-3, or LTO-4 Ultrium tape cartridges

• BladeSystem PCI Expansion Blade that holds two off-the-shelf PCI-X or PCIe cards