1)查看RLDP的状态

2)假设g0/5和g0/7口环起来后会出现如下log
Rujijie#
*Mar 19 20:16:00: %RLDP-3-LINK_DETECT_ERROR: loop detection error detect on interface GigabitEthernet 0/7.set this interface errordisable!
*Mar 19 20:16:00: %RLDP-3-LINK_DETECT_ERROR: loop detection error detect on interface GigabitEthernet 0/5.set this interface errordisable!
Mar 19 20:16:01: %LINEPROTO-5-UPDOWN: Line protocol on Interface VLAN 1, changed state to down.
*Mar 19 20:16:02: %LINK-3-UPDOWN: Interface GigabitEthernet 0/5, changed state to down.
*Mar 19 20:16:02: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet 0/5, changed state to down.
*Mar 19 20:16:02: %LINK-3-UPDOWN: Interface GigabitEthernet 0/7, changed state to down.
*Mar 19 20:16:02: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet 0/7, changed state to down.
3)查看接口状态,发现这两个口被disable了

4、过了默认的300S时间后,交换机会把端口自动变为恢复状态
*Mar 19 20:21:01: %PORT_SECURITY-4-ERR_RECOVER: Interface GigabitEthernet 0/5 recover from an error.
*Mar 19 20:21:01: %PORT_SECURITY-4-ERR_RECOVER: Interface GigabitEthernet 0/7 recover from an error.
*Mar 19 20:21:01: %RLDP-3-LINK_DETECT_RECOVER: rldp recover interface GigabitEthernet 0/7 from loop error
*Mar 19 20:21:01: %RLDP-3-LINK_DETECT_RECOVER: rldp recover interface GigabitEthernet 0/5 from loop error
*Mar 19 20:21:04: %LINEPROTO-5-UPDOWN: Line protocol on Interface VLAN 1, changed state to up.
*Mar 19 20:21:06: %LINK-3-UPDOWN: Interface GigabitEthernet 0/5, changed state to up.
*Mar 19 20:21:06: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet 0/5, changed state to up.
*Mar 19 20:21:06: %LINK-3-UPDOWN: Interface GigabitEthernet 0/7, changed state to up.
*Mar 19 20:21:06: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet 0/7, changed state to up.
5)如果需要立即恢复被disable的端口,可以通过如下命令实现
Rujijie#rldp reset 或者 Ruijie(config)#errdisable recovery
*Mar 19 20:34:32: %PORT_SECURITY-4-ERR_RECOVER: Interface GigabitEthernet 0/7 recover from an error.
*Mar 19 20:34:32: %RLDP-3-LINK_DETECT_RECOVER: rldp recover interface GigabitEthernet 0/7 from loop error
*Mar 19 20:34:32: %PORT_SECURITY-4-ERR_RECOVER: Interface GigabitEthernet 0/5 recover from an error.
*Mar 19 20:34:32: %RLDP-3-LINK_DETECT_RECOVER: rldp recover interface GigabitEthernet 0/5 from loop error