Although it wasn’t the first to enter the blade server market, HP has set a number of standards not least in build quality and features and its latest BL20 p-Class looks to continue this tradition. Introduced in 2002, the more compact BL10 e-Class blade server is aimed at server clustering and providing enterprise networks or corporate data centres with utility services. The new BL20 is primarily targeted at service provision applications and now competes directly with IBM’s BladeCentre products by delivering Xeon-based blade servers. Although not as high as the BladeCentre’s chassis the BL20 still comes in at 6U and supports up to eight blades. However, before you whip out the calculator to check on maximum processing density you’ll need to factor in power requirements as the BL20 uses a separate 3U high chassis. HP has indulged in a bit of forward thinking here as it has designed the power systems to provide not only unbeatable fault tolerance but has also added in sufficient surplus to allow it to power the next generations of Xeon processors. There are plenty of options as you can choose a chassis that supports up to four single-phase supplies or a three-phase version that can accommodate six hot-plug supplies and with the use of bus-bars power is designed to be distributed to multiple blade servers. A typical scenario would be a pair of power chassis supplying the juice to six fully populated BL20 chassis resulting in a Xeon density of 96 per industry standard rack. The blades are amongst the largest we’ve seen but this is due to them containing every component you’d expect in a server including their own cooling fans. The processors are mounted behind these and on the review system these were a pair of 2.8GHz Xeons each equipped with large passive heatsinks. Four memory sockets are located further back and came fitted with 1GB of PC2100 SDRAM which can be expanded to 8GB. Hard disk storage is also responsible for the increased blade size as each of the six blades supplied to us came with a pair of 18GB Ultra320 SCSI drives mounted in hot-swap carriers and protected by an integrated HP Smart Array 5i RAID controller supporting RAID-0 or -1 arrays. Network connections are plentiful as each blade sports three 10/100BaseTX adapters for general use plus a fourth that is dedicated to HP’s iLO (integrated lights out) remote management. Local blade access is also possible by connecting a small unit with serial port and 10/100BaseTX crossover port. Along with the eight blade slots, two more slots at each end of the chassis are fitted with GBe interconnect modules that function as Layer 2 switches and can be accessed and configured remotely via a browser. These are designed to take each blade’s three network ports and link them to the four QuadT network modules located at the rear that each provides four Gigabit Ethernet connections. With so many servers to play with, software deployment and management needs to be good and HP excels in this area with its Rapid Deployment Pack (RDP) which is built around Altiris’ eXpress Deployment Server application. HP includes a ProLiant integration module which customises the package for swift delivery of operating systems to the BL20 and during RDP installation you can select which OSes you want images created of. Ensure each blade contacts a DHCP server during boot-up and it will be displayed in the Deployment Server interface ready to receive software and all you do is drag a predefined script from the list, drop it onto the relevant server icon and sit back while the RDP initiates a fully automated network OS install. Help desk tools are immediately available as an agent is also loaded onto each server for remote access. General server monitoring and management is handled by HP’s Insight Manager 7 software which provides plenty of operational information on each system from its tidy secure browser interface and can send out alerts if it detects any hardware related problems. The BL20 p-Class is yet another impressive piece of blade server engineering from HP. It may only offer a comparatively low processing density but it more than makes up for this with excellent management and software deployment tools plus superb levels of redundancy.


The blade server is primarily designed to maximize floor space by packing all your servers into as small an area as possible. There is a wide range of choice currently on the market and if processing density is more important then look elsewhere – HP’s BL10 e-Class or the Fujitsu Siemens BX300 are prime candidates. However, if Xeon processing and mainframe strength build quality and fault tolerance are key requirements than look no further than the BL20 p-Class.