HP XC System Software 3.2.1 manual Switches, Specialized Switch Use

to create a higher bandwidth connection between the Root Administration Switches and the Branch Administration Switches.

For physically small hardware models (such as a 1U HP ProLiant DL145 server), a large number of servers (more than 30) can be placed in a single cabinet, and are all attached to a single branch switch. The branch switch is a ProCurve Switch 2848, and two-port trunking is used for the connection between the Branch Administration Switch and the Root Administration Switch.

For physically larger hardware models (2U and larger) such the HP Integrity rx2600 and HP ProLiant DL585 servers, a smaller number of servers can be placed in a single cabinet. In this case, the branch switch is a ProCurve Switch 2824, which is sufficient to support up to 19 nodes.

In this release, the HP XC System Software supports the use of multiwire connections or trunks between switches in the system. In a large-scale system (one that has regions and uses a super root switch), you can use a one-wire to four-wire trunk between the super root switch and the root administration switch for each of the HP XC regions. On a smaller-scale HP XC system or within a single region, one-wire and two-wire trunks are supported for connection between the root administration switch and the branch administration switches.

You must configure trunks on both switches before plugging the cables in between the switches. Otherwise, a loop is created between the switches, and the network is rendered useless.

Trunking configurations on switches must follow these guidelines:

•Because of the architecture of the ProCurve switch, the HP XC System Software uses only 10 ports of each 12-port segment to ensure maximum bandwidth through the switch; the last two ports are not used.

•Trunk groups must be contiguous.

Thus, by adhering to the trunking guidelines, the following ports are used to configure a ProCurve

2848 Super Root Switch for three regions using four-wire trunks:

•Region 1 - Ports 1, 2, 3, 4

•Region 2 - Ports 5, 6, 7, 8

•Region 3 - Ports 13, 14, 15, 16

•Ports 9, 10, 11, and 12 are not used

3.3Switches

The following topics are addressed in this section:

•“Specialized Switch Use” (page 46)

•“Administrator Passwords on ProCurve Switches” (page 47)

•“Switch Port Connections” (page 47)

•“Switch Connections and HP Workstations” (page 49)

•“Super Root Switch” (page 49)

•“Root Administration Switch” (page 50)

•“Root Console Switches” (page 51)

•“Branch Administration Switches” (page 54)

•“Branch Console Switches” (page 55)

3.3.1Specialized Switch Use

The following describes the specialized uses of switches in an HP XC system.

Super Root Switch	This switch is the top level switch in a large-scale system,
	that is, an HP XC system with more than 512 nodes
	requiring more than one Root Administration switch.
	Root Administration switches are connected directly to
	this switch.

46 Making Node and Switch Connections