Specifications

In order to prevent downtime due to I/O errors, HP has designed the following features into the

rp8400:

• online replacement of PCI cards

• hardware “firewall” of I/O errors to cell

• high-MTBF (mean time between failures) I/O cards

• separate PCI buses for each I/O card

Taken together, these features will reduce hardware downtime by at least 20 percent over similar

servers.

online replacement of PCI cards

PCI cards in the rp8400 can be added and replaced online at introduction, with delete capability

planned for a future HP-UX release. Online replacement reduces planned downtime by allowing

the online addition of resources to a running system and the ability to replace a failed card

without bringing down the system.

hardware “firewall” to limit I/O errors

No I/O card in the rp8400 shares a PCI bus with any other card. In other words, all I/O cards are

logically and electrically isolated from all other PCI cards. This significantly improves performance,

reduces the likelihood of I/O errors, and confines errors to a single PCI bus and card.

high-MTBF I/O cards

HP’s I/O cards are extensively qualified to work in our servers. This means stringent MTBF goals

and full interoperability testing of all I/O cards: no incompatible drivers, no bad pointers, and no

marginal signal quality.

crossbar backplane

The backplane ties CPU and memory together. Because all partitions share the backplane, high

protection

reliability and true domain isolation are very important. The specific features that address these

areas are:

• highly reliable ASICs

• redundant dc-dc converters

• full end-to-end error correction and independent-partition design