Configuring the hybrid port shutdown mode

Network requirements

As shown in Figure 12, Device A and Device B are connected through two fiber pairs.

Configure DLDP to detect unidirectional links. When a unidirectional link is detected, DLDP automatically shuts down the unidirectional port. The administrator needs to bring up the port after clearing the fault.

Figure 12: Network diagram

Configuration procedure

  1. Configure Device A:

    # Enable DLDP globally.

    <DeviceA> system-view
    [DeviceA] dldp enable
    

    # Configure GigabitEthernet 1/0/1 to operate in full duplex mode and at 1000 Mbps, and enable DLDP on the port.

    [DeviceA] interface gigabitethernet 1/0/1
    [DeviceA-GigabitEthernet1/0/1] duplex full
    [DeviceA-GigabitEthernet1/0/1] speed 1000
    [DeviceA-GigabitEthernet1/0/1] dldp enable
    [DeviceA-GigabitEthernet1/0/1] quit
    

    # Configure GigabitEthernet 1/0/2 to operate in full duplex mode and at 1000 Mbps, and enable DLDP on the port.

    [DeviceA] interface gigabitethernet 1/0/2
    [DeviceA-GigabitEthernet1/0/2] duplex full
    [DeviceA-GigabitEthernet1/0/2] speed 1000
    [DeviceA-GigabitEthernet1/0/2] dldp enable
    [DeviceA-GigabitEthernet1/0/2] quit
    

    # Set the port shutdown mode to hybrid.

    [DeviceA] dldp unidirectional-shutdown hybrid
    
  2. Configure Device B:

    # Enable DLDP globally.

    <DeviceB> system-view
    [DeviceB] dldp global enable
    

    # Configure GigabitEthernet 1/0/1 to operate in full duplex mode and at 1000 Mbps, and enable DLDP on it.

    [DeviceB] interface gigabitethernet 1/0/1
    [DeviceB-GigabitEthernet1/0/1] duplex full
    [DeviceB-GigabitEthernet1/0/1] speed 1000
    [DeviceB-GigabitEthernet1/0/1] dldp enable
    [DeviceB-GigabitEthernet1/0/1] quit
    

    # Configure GigabitEthernet 1/0/2 to operate in full duplex mode and at 1000 Mbps, and enable DLDP on it.

    [DeviceB] interface gigabitethernet 1/0/2
    [DeviceB-GigabitEthernet1/0/2] duplex full
    [DeviceB-GigabitEthernet1/0/2] speed 1000
    [DeviceB-GigabitEthernet1/0/2] dldp enable
    [DeviceB-GigabitEthernet1/0/2] quit
    

    # Set the port shutdown mode to hybrid.

    [DeviceB] dldp unidirectional-shutdown hybrid
    

Verifying the configuration

# Display the DLDP configuration globally and on all the DLDP-enabled ports of Device A.

[DeviceA] display dldp
 DLDP global status: Enabled
 DLDP advertisement interval: 5s
 DLDP authentication-mode: None
 DLDP unidirectional-shutdown mode: Manual
 DLDP delaydown-timer value: 1s
 Number of enabled ports: 2

Interface GigabitEthernet1/0/1
 DLDP port state: Bidirectional
 Number of the port’s neighbors: 1
  Neighbor MAC address: 0023-8956-3600
  Neighbor port index: 1
  Neighbor state: Confirmed
  Neighbor aged time: 11s

Interface GigabitEthernet1/0/2
 DLDP port state: Bidirectional
 Number of the port’s neighbors: 1
  Neighbor MAC address: 0023-8956-3600
  Neighbor port index: 2
  Neighbor state: Confirmed
  Neighbor aged time: 12s

The output shows that both GigabitEthernet 1/0/1 and GigabitEthernet 1/0/2 are in Bidirectional state, which means both links are bidirectional.

# Enable the monitoring of logs on the current terminal on Device A. Set the lowest level of the logs that can be output to the current terminal to 6.

[DeviceA] quit
<DeviceA> terminal monitor
<DeviceA> terminal logging level 6

The following log information is displayed on Device A:

  <DeviceA>%Jan  4 07:16:06:556 2011 DeviceA DLDP/5/DLDP_NEIGHBOR_AGED: A neighbor on interface
GigabitEthernet1/0/1 was deleted because the neighbor was aged. The neighbor's system MAC is 0023-8956-3600, and the port index is 162.
%Jan  4 07:16:06:560 2011 DeviceA DLDP/5/DLDP_NEIGHBOR_AGED: A neighbor on interface
GigabitEthernet1/0/2 was deleted because the neighbor was aged. The neighbor's system MAC is 0023-8956-3600, and the port index is 165.
%Jan  4 07:16:06:724 2011 DeviceA IFNET/3/PHY_UPDOWN: Physical state on the interface GigabitEthernet1/0/1 changed to down.
%Jan  4 07:16:06:730 2011 DeviceA IFNET/3/PHY_UPDOWN: Physical state on the interface GigabitEthernet1/0/2 changed to down.
%Jan  4 07:16:06:736 2011 DeviceA IFNET/5/LINK_UPDOWN: Line protocol state on the interface GigabitEthernet1/0/1 changed to down.
%Jan  4 07:16:06:738 2011 DeviceA IFNET/5/LINK_UPDOWN: Line protocol state on the interface GigabitEthernet1/0/2 changed to down.
%Jan  4 07:16:07:152 2011 DeviceA DLDP/3/DLDP_LINK_UNIDIRECTIONAL: DLDP detected a unidirectional link on interface GigabitEthernet1/0/1. DLDP automatically shut down the interface. Please manually bring up the interface.
%Jan  4 07:16:07:156 2011 DeviceA DLDP/3/DLDP_LINK_UNIDIRECTIONAL: DLDP detected a unidirectional link on interface GigabitEthernet1/0/2. DLDP automatically shut down the interface. Please manually bring up the interface.

The output shows that the port status and link status of both GigabitEthernet 1/0/1 and GigabitEthernet 1/0/2 are down.

# Display the DLDP configuration globally and of all the DLDP-enabled ports.

<DeviceA> display dldp
 DLDP global status: Enabled
 DLDP advertisement interval: 5s
 DLDP authentication-mode: None
 DLDP unidirectional-shutdown mode: Hybrid
 DLDP delaydown-timer value: 1s
 Number of enabled ports: 2

Interface GigabitEthernet1/0/1
 DLDP port state: Inactive
 Number of the port's neighbors: 0 (Maximum number ever detected: 1)
Interface GigabitEthernet1/0/2
 DLDP port state: Inactive
 Number of the port's neighbors: 0 (Maximum number ever detected: 1)

The output shows that DLDP detects a unidirectional link and shuts down GigabitEthernet 1/0/1 and GigabitEthernet 1/0/2.

The unidirectional links are caused by cross-connected fibers. Bring up the two ports after correct the fiber connection:

# Bring up GigabitEthernet 1/0/1.

<DeviceA> system-view
[DeviceA] interface gigabitethernet 1/0/1
[DeviceA-GigabitEthernet1/0/1] undo shutdown

The following log information is displayed on Device A:

[DeviceA-GigabitEthernet1/0/1]%Jan  4 07:33:26:574 2011 DeviceA IFNET/3/PHY_UPDOWN: Physical state on the interface GigabitEthernet1/0/1 changed to up.
%Jan  4 07:33:57:562 2011 DeviceA DLDP/6/DLDP_NEIGHBOR_CONFIRMED: A neighbor was confirmed on interface GigabitEthernet1/0/1. The neighbor's system MAC is 0023-8956-3600, and the port index is 162.
%Jan  4 07:33:57:563 2011 DeviceA DLDP/6/DLDP_LINK_BIDIRECTIONAL: DLDP detected a bidirectional link on interface GigabitEthernet1/0/1.
%Jan  4 07:33:57:590 2011 DeviceA IFNET/5/LINK_UPDOWN: Line protocol state on the interface GigabitEthernet1/0/1 changed to up.
%Jan  4 07:33:57:609 2011 DeviceA STP/6/STP_DETECTED_TC: Instance 0's port GigabitEthernet1/0/1 detected a topology change.

The output shows that the port status and link status of GigabitEthernet 1/0/1 are now up and its DLDP neighbors are determined.

# Bring up GigabitEthernet 1/0/2.

[DeviceA-GigabitEthernet1/0/1] quit
[DeviceA] interface gigabitethernet 1/0/2
[DeviceA-GigabitEthernet1/0/2] undo shutdown

The following log information is displayed on Device A:

[DeviceA-GigabitEthernet1/0/2]%Jan  4 07:35:26:574 2011 DeviceA IFNET/3/PHY_UPDOWN: Physical state on the interface GigabitEthernet1/0/2 changed to up.
%Jan  4 07:35:57:562 2011 DeviceA DLDP/6/DLDP_NEIGHBOR_CONFIRMED: A neighbor was confirmed on interface GigabitEthernet1/0/2. The neighbor's system MAC is 0023-8956-3600, and the port index is 162.
%Jan  4 07:35:57:563 2011 DeviceA DLDP/6/DLDP_LINK_BIDIRECTIONAL: DLDP detected a bidirectional link on interface GigabitEthernet1/0/2.
%Jan  4 07:35:57:590 2011 DeviceA IFNET/5/LINK_UPDOWN: Line protocol state on the interface GigabitEthernet1/0/2 changed to up.
%Jan  4 07:35:57:609 2011 DeviceA STP/6/STP_DETECTED_TC: Instance 0's port GigabitEthernet1/0/2 detected a topology change.

The output shows that the port status and link status of GigabitEthernet 1/0/2 are now up and its DLDP neighbors are determined.