1 oversubscription – Brocade FastIron SX Series Chassis Hardware Installation Guide User Manual
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CAUTION
It is important to wait a minimum of 10 seconds between the removal and insertion of a line
module. Re-insertion of a line module less than 10 seconds after the removal of a line module
may result in the line module not being properly recognized.
on page 124 for instructions.
48-port 10/100/1000 Mbps (RJ45) Ethernet PoE interface module
The 48-port 10/100/1000 Mbps Ethernet PoE interface module (SX-FI48GPP) uses two vertical half-
slots in the FastIron SX 800 or 1600 device and is supported in IPv4-only and IPv6-capable systems.
The ports support automatic MDI or MDIX detection, and use auto-sensing and auto-negotiating to
determine the speed (10, 100, or 1000 Mbps) and duplex mode (full-duplex or half-duplex) of the port
at the other end of the link, and adjust the local port accordingly. Ports running at 1000 Mbps operate
in full-duplex mode only and cannot be modified.
The module is 2:1 oversubscribed with an intelligent queue in front of the module packet processor.
Traffic on each port can be classified as high or low priority, and can be scheduled from a queue using
these priority settings ensuring QoS from the port of entry into the network.
2:1 oversubscription
Interface oversubscription is the use of a single physical ingress port to handle incoming traffic from
multiple devices, and is usually expressed as a ratio; the ratio shows the proportion of incoming
connections to physical ports carrying traffic to the backplane of the device. The FastIron supports 2:1
oversubscription, allowing two devices to pass traffic through a single internal physical port to take
advantage of bandwidth which might otherwise go unused.
Oversubscription is achieved on the SX-FI48GPP by connecting 48 external ports to 24 internal
physical ports, providing 2:1 oversubscription. No CLI command is required to enable
oversubscription, but because two external ports are funneling traffic into each physical link, the
FastIron uses virtual interfaces (VEs) to divide each physical link into two logical ports. These VEs can
then be individually configured at the interface level.
NOTE
This interface module is supported only on the FSX-800 and FSX-1600.
FIGURE 8 48-port 10/100/1000 Mbps Ethernet PoE interface module front panel
48-port 10/100/1000 Mbps (RJ45) Ethernet PoE interface module
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Brocade FastIron SX Series Chassis Hardware Installation Guide
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