4-13
Cisco MDS 9000 Family NX-OS Interfaces Configuration Guide
OL-29284-01, Release 6.x
Chapter 4 Configuring Interface Buffers
Information About Interface Buffers
Figure 4-8 Example Speed and Rate Configuration on a 24-Port 4-Gbps Switching Module
18-Port Fibre Channel/4-Port Gigabit Ethernet Multiservice Module BB_Credit Buffers
Table 4-7 lists the BB_credit buffer allocation for 18-port 4-Gbps multiservice modules.
The following considerations apply to BB_credit buffers on18-port 4-Gbps Fibre Channel switching
modules:
• BB_credit buffers for ISL connections can be configured from a minimum of 2 buffers to a
maximum of 250 buffers for dedicated rate mode or 16 buffers for shared 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 16 buffers for shared rate mode.
• Performance buffers are not supported on this module.
12-Port 4-Gbps Switching Module BB_Credit Buffers
Table 4-8 lists the BB_credit buffer allocation for 12-port 4-Gbps switching modules.
4-Gbps 4-Gbps 4-Gbps 1-Gbps 1-Gbps 1-Gbps
Dedicated Dedicated Dedicated
Shared
Shared
Shared
1
23 456
144857
Ta b l e 4-7 18-Port 4-Gbps Multiservice Module BB_Credit Buffer Allocation
BB_Credit Buffer Allocation
BB_Credit Buffers Per Port
Dedicated Rate Mode
4-Gbps Speed
Shared Rate Mode
4-Gbps Speed
ISL
1
1. ISL = E port or TE port.
Fx Port ISL
1
Fx Port
Default BB_credit buffers 250 16 16 16
Maximum BB_credit buffers 250 250 16 16
Total number of BB_credit buffers per module 4509
Ta b l e 4-8 12-Port 4-Gbps Switching Module BB_Credit Buffer Allocation
BB_Credit Buffer Allocation Type
BB_Credit Buffers Per Port
Dedicated Rate Mode
4-Gbps Speed
ISL
1
Fx Port
Default BB_credit buffers 250 16
Maximum BB_credit buffers 250 16
Default Performance buffers 145 12
