Optimizing The 10-Gbe Port Configuration - HP 5400 zl Installation And Getting Started Manual

Optimizing the 10-GbE Port Configuration

The 10-GbE ports on the HP 5400 zl switch are designed to deliver full 10 Gbps
wire-speed to each port, where either one or two ports are in a linked state
with another device. When three or four 10-GbE ports are in a linked state,
when using an X2 (J8708A), CX4 (J8707A) or SFP+ (J9309A) module, the 10-
GbE ports support an aggregate bandwidth of 28.8 Gbps across the linked
ports.
As illustrated in the figure below, internally, there are two 14.4-Gbps channels
between each of the 4 10-GbE ports and the switch fabric.
Figure 2-19. 10-GbE port architecture showing ports grouped by 14.4 Gbps channel.
When any two 10-GbE ports are in a linked state, each port automatically
operates on its own channel, which guarantees 10 Gbps of bandwidth for each
port. However, when more than two ports are in a linked state, ports A1 and
A4 are statically mapped to share one 14.4 Gbps channel, while ports A2 and
A3 are statically mapped to share the other 14.4 Gbps channel.
To summarize:
If only one port in a given channel is in a linked state, then that port
■
operates at wire speed and the other port uses no bandwidth.
■ If both ports in a given channel are in a linked state, then the 14.4 Gbps of
bandwidth is balanced fairly between the two ports.
For example, in an application where three ports are needed and it is impor-
tant to ensure that port 1 always has a full 10 Gbps available, the connection
choices shown in the next figure would be used.
Installing the HP 5400 zl Switches
Example Network Topologies
2-29