For proper operation, FA must be enabled at both the global level and at the interface level on the FA Server. By default, FA is globally enabled. However, FA is disabled by default at the interface level and must be explicitly enabled on each interface.
Use this procedure to enable Fabric Attach globally on a switch.
enable
configure terminal
fa enable
no fa enable

Caution
Disabling FA flushes all FA element discovery and mappings.
show fa
show fa agent
Switch:1>en Switch:1#conf t Enter configuration commands, one per line. End with CNTL/Z. Switch:1(config)#fa enable
Switch:1>show fa
================================================================================
                          Fabric Attach Configuration
================================================================================
                            FA Service : enabled
                       FA Element Type : server
                 FA Assignment Timeout : 240
                  FA Discovery Timeout : 240
                     FA Provision Mode : spbm
         Switch:1>show fa agent
================================================================================
                          Fabric Attach Configuration
================================================================================
                            FA Service : enabled
                       FA Element Type : server
                 FA Assignment Timeout : 240
                  FA Discovery Timeout : 240
                     FA Provision Mode : spbm