HP XC System Software Hardware Preparation Guide Version 2.1

The head no de is always the node connected to the highest port number of any node on the Root
Administration Switch and the R oot Console Switch.
_________________________ Note _________________________
The head node port is not the highest port num ber on the Root Administration
Switch. Other higher port num bers are used to connect to other switches. If the
Root Administration Switch is a ProCurve 2848 switch, the head node is connected
to port number 42, as discussed in Section 2.3.1.
If the Root Administration Switch is a ProCurve 282 4 switch, the head node is
connected to port number 22 on that switch, as discussed in Section 2.3.1. The
head node should, however, be connected to the highest port numb er on the
interconnect switch.
The next node connected directly to the root switches (Ad mi nistration and Console) should
have connections to the Qu adrics switch at the next h igh est port number on the Quadrics
switch (max-node minus 2). All nodes co nnected to the Root Administration Switch will be
connected to the next port in descending order.
Nodes attached to branch switches must be connected starting at the opposite end of the
Quadrics switch. The node attached to the first port of the first Branch Administration Switch
should be attached to the first port on the Quadrics switch (Port 0).
2.4.2 Gigabit Ethernet Interconnect Connections
The HP XC System Software is not concerned with the topology of the Gigabit Eth ernet
interconnect, but it makes sense to structure it in parallel with the System A dministration
network in order to make your connections easy to maintain.
Because the first logical Gigabit Ethernet port on each node is always used for connectivity to
the System Administration network, there must be a second Gigabit Ethernet port on each node
if you are using Gigabit Ethernet as the interconnect.
This may be a built-in port, as wit h the HP ProLiant DL145 ser ver, the HP ProLiant D L585
server, and HP ProLiant DL360 G 4 and DL380 G4 servers; or it may be an installed card, as
with the HP Integrity rx2600 server. Any node with an external interface must also have a third
Ethernet connection of any kind to communicate with external networks.
2.4.3 Administrative Network Interconnect Connections
In cases where an additional Gigabit Ethernet port or switch may not be available, the HP XC
System Software allows the interconnect to be configured on the Administrative Network.
However, be aware that doing so may negatively impact system performance.
2.4.4 Other Interconnect Connections
The other interconnect types that are supported (such as Myrinet and In finiBand) do not have the
ordering requirements of the Quadrics interconnect, but it makes sense to structure it in parallel
with the other two networks in order to make your connections easy to maintain and service.
The port numbering on these other interconnect switches starts at number 1 in contrast to the
port numbering on the Quadrics interconnect switch, which starts at number 0.
Making Node and Switch Connections 2-9