FC ID Allocation for HBAs
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
Configuring a Secondary MAC Address
To allocate secondary MAC addresses, follow these steps:
switch# config t
switch(config)# wwn secondary-mac 00:99:55:77:55:55 range 64
This command CANNOT be undone.
Please enter the BASE MAC ADDRESS again: 00:99:55:77:55:55
Please enter the mac address RANGE again: 64
From now on WWN allocation would be based on new MACs.
Are you sure? (yes/no) no
You entered: no. Secondary MAC NOT programmed
FC ID Allocation for HBAs
Fibre Channel standards require a unique FC ID to be allocated to an N port attached to a Fx port in any
switch. To conserve the number of FC IDs used, Cisco MDS 9000 Family switches use a special
Some HBAs do not discover targets that have FC IDs with the same domain and area. Prior to Cisco
SAN-OS Release 2.0(1b), the Cisco SAN-OS software maintained a list of tested company IDs that do
not exhibit this behavior. These HBAs were allocated with single FC IDs, and for others a full area was
The FC ID allocation scheme available in Release 1.3 and earlier, allocates a full area to these HBAs.
This allocation isolates them to that area and are listed with their pWWN during a fabric login. The
allocated FC IDs are cached persistently and are still available in Cisco SAN-OS Release 2.0(1b) (see
To allow further scalability for switches with numerous ports, the Cisco SAN-OS software maintains a
list of HBAs exhibiting this behavior. Each HBA is identified by its company ID (also know as
Organizational Unique Identifier, or OUI) used in the pWWN during a fabric log in. Hence a full area is
allocated to the N ports with company IDs that are listed and for the others, a single FC ID is allocated.
Irrespective of the kind (whole area or single) of FC ID allocated, the FC ID entries remain persistent.
This section includes the following topics:
Default Company ID list
All switches in the Cisco MDS 9000 Family that ship with Cisco SAN-OS Release 2.0(1b) or later,
contain a default list of company IDs that require area allocation. Using the company ID reduces the
number of configured persistent FC ID entries. You can configure or modify these entries using the CLI.
Cisco MDS 9000 Family CLI Configuration Guide
"FC ID Allocation for HBAs" section on page
Default Company ID list, page 29-10
Verifying the Company ID Configuration, page 29-11
Advanced Features and Concepts
Enters configuration mode.
Configures the secondary MAC
address. This command cannot
OL-16184-01, Cisco MDS SAN-OS Release 3.x