Brocade Web Tools Administrator's Guide (53-0000194-01, November 2006)

Web Tools Administrator’s Guide 14-1
Publication Number: 53-0000194-01
Chapter
14
Administering Extended Fabrics
This chapter contains the following information:
• “About Extended Link Buffer Allocation,” next
• “Configuring a Port for Long Distance” on page 14-3
About Extended Link Buffer Allocation
As the distance between switches and the link speed increases, additional buffer-to-buffer credits are
required to maintain maximum performance. The number of credits reserved for a port depends on the
switch model and on the extended ISL mode for which it is configured.
The Extended Fabric tab of the Switch Admin module displays information about the port speed, long-
distance setting, and buffer credits, as shown in Figure 14-1 on page 14-2. Use this tab to configure the
long-distance setting of a port. For detailed information on managing extended fabrics, see the Fabric
OS Administrator’s Guide.
The Extended Fabric tab displays the following information:
• Port Number
• Buffer Limited—Indicates whether the port is buffer limited. A buffer-limited port can come online
with fewer buffer credits allocated than its configuration specifies, allowing it to operate at a
reduced bandwidth instead of being disabled for lack of buffers.
Buffer-limited operation is supported for the L0 and LD extended ISL modes only and is persistent
across reboots, switch disabling and enabling, and port disabling and enabling.
• Port Speed—The port speed is displayed as follows:
- 1G—1 Gbit/sec
- 2G—2 Gbit/sec
- 4G—4 Gbit/sec
- N1—Negotiated 1 Gbit/sec
- N2—Negotiated 2 Gbit/sec
N
ote
Because buffer credits are a switch resource, you must own the switch in order to modify Extended
Fabric settings on a port.
N
ote
You do not need to use the Extended Fabrics feature unless the link is used over long distances.