Cisco Systems DSC9148D8G48PK9 manual Three ports with dedicated rate mode and 4-Gbps speed

Chapter 4 Configuring Interface Buffers

Information About Interface Buffers

•Three ports with dedicated rate mode and 4-Gbps speed

4/44-Port 8-Gbps Host-Optimized Fibre Channel Module BB_Credit Buffers

Table 4-4lists the BB_credit buffer allocation for the 4/44-port 8-Gbps Fibre Channel switching module.

Table 4-4 4/44-Port 8-Gbps Switching Module BB_Credit Buffer Allocation

	BB_Credit Buffers Per Port
	Dedicated Rate Mode		Shared Rate Mode
	8-Gbps Speed		8-Gbps Speed
BB_Credit Buffer Allocation	ISL	Fx Port	Fx Port
Default BB_credit buffers	125	32	32
Maximum BB_credit buffers	250	250	32
Total number of BB_credit buffers per module	6000

The following guidelines apply to BB_credit buffers on 4/44-port 8-Gbps Fibre Channel switching modules:

•BB_credit buffers for ISL connections can be configured from a minimum of 2 buffers to a maximum of 500 buffers for dedicated rate mode.

•BB_credit buffers for Fx port mode connections can be configured. The minimum is 2 buffers and the maximum of 250 buffers for dedicated rate mode or 32 buffers for shared rate mode.

•Performance buffers are not supported on this module.

Each port group on the 24-port 8-Gbps Fibre Channel switching module consists of 12 ports. The ports in shared rate mode in a port group can have a maximum bandwidth oversubscription of 10:1 considering that each port group has 12.8-Gbps bandwidth.

The following example configurations are supported by the 4/44-port 8-Gbps Fibre Channel switching modules:

•Twelve ports with shared rate mode and 4-Gbps speed (5:1 oversubscription) (default)

•One port with dedicated rate mode and 8-Gbps speed plus

eleven ports with shared rate mode and 4-Gbps speed (10:1 oversubscription)

•One port with dedicated rate mode and 4-Gbps speed plus three ports with dedicated rate mode and 3-Gbps speed plus

eight ports with shared rate mode and 4-Gbps speed (2:1 oversubscription)

•Twelve ports with dedicated rate mode and 1-Gbps speed

	Cisco MDS 9000 Family NX-OS Interfaces Configuration Guide
OL-29284-01, Release 6.x		4-9