Use the following procedure to display the admin status of the Gateway.
show isis spbm
Switch:1>show isis spbm
============================================================================================
                                 ISIS SPBM Info
============================================================================================
SPBM       B-VID      PRIMARY    NICK     LSDB     IP       IPV6     MULTICAST   SPB-PIM-GW
INSTANCE              VLAN       NAME     TRAP    
--------------------------------------------------------------------------------------------
1          10,20      10         0.00.77  disable  enable   disable  enable      Gateway
============================================================================================
                              ISIS SPBM SMLT Info
============================================================================================
SPBM       SMLT-SPLIT-BEB       SMLT-VIRTUAL-BMAC     SMLT-PEER-SYSTEM-ID
INSTANCE  
--------------------------------------------------------------------------------------------
1          primary              00:00:00:00:00:00                        
--------------------------------------------------------------------------------
 Total Num of SPBM instances: 1
--------------------------------------------------------------------------------
If the controller and gateway are both enabled on the node
Switch:1>show isis spbm
============================================================================================
                                 ISIS SPBM Info
============================================================================================
SPBM       B-VID      PRIMARY    NICK     LSDB     IP       IPV6     MULTICAST   SPB-PIM-GW
INSTANCE              VLAN       NAME     TRAP    
--------------------------------------------------------------------------------------------
1          10,20      10         0.00.77  disable  enable   disable  enable      controller																																	/gateway
============================================================================================
                              ISIS SPBM SMLT Info
============================================================================================
SPBM       SMLT-SPLIT-BEB       SMLT-VIRTUAL-BMAC     SMLT-PEER-SYSTEM-ID
INSTANCE  
--------------------------------------------------------------------------------------------
1          primary              00:00:00:00:00:00                        
--------------------------------------------------------------------------------
 Total Num of SPBM instances: 1
--------------------------------------------------------------------------------