我对stp（生成树协议）有问题，大多数时候我们总是将端口设置为stp enable。但在下面的开关下，每个端口都设置为stp disable。我想知道什么时候设置stp disable。谢谢！

#               
interface GigabitEthernet1/0/1
 port link-mode bridge
 port access vlan 1000
 stp disable    
 arp detection trust
#               
interface GigabitEthernet1/0/2
 port link-mode bridge
 port access vlan 1000
 stp disable    
 arp detection trust
#               
interface GigabitEthernet1/0/3
 port link-mode bridge
 port access vlan 1000
 stp disable    
#               
interface GigabitEthernet1/0/4
 port link-mode bridge
 port access vlan 3
#               
interface GigabitEthernet1/0/5
 port link-mode bridge
 port access vlan 3
#               
interface GigabitEthernet1/0/6
 port link-mode bridge
 port access vlan 4
 stp disable    
#               
interface GigabitEthernet1/0/7
 port link-mode bridge
 port access vlan 1000
 stp disable    
#               
interface GigabitEthernet1/0/8
 port link-mode bridge
 port access vlan 1000
 stp disable