Example: Configuring the hybrid port shutdown mode

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.

	IMPORTANT: By default, interfaces on the device are disabled (in ADM or Administratively Down state). To have an interface operate, you must use the undo shutdown command to enable that interface.

1. Configure Device A:

   # Enable DLDP globally.

   <DeviceA> system-view
   [DeviceA] dldp enable
   

   # Configure FortyGigE 1/0/1 to operate in full duplex mode and at 40000 Mbps, and enable DLDP on the port.

   [DeviceA] interface fortygige 1/0/1
   [DeviceA-FortyGigE1/0/1] duplex full
   [DeviceA-FortyGigE1/0/1] speed 40000
   [DeviceA-FortyGigE1/0/1] dldp enable
   [DeviceA-FortyGigE1/0/1] quit
   

   # Configure FortyGigE 1/0/2 to operate in full duplex mode and at 40000 Mbps, and enable DLDP on the port.

   [DeviceA] interface fortygige 1/0/2
   [DeviceA-FortyGigE1/0/2] duplex full
   [DeviceA-FortyGigE1/0/2] speed 40000
   [DeviceA-FortyGigE1/0/2] dldp enable
   [DeviceA-FortyGigE1/0/2] quit
   

   # Set the global 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 FortyGigE 1/0/1 to operate in full duplex mode and at 40000 Mbps, and enable DLDP on it.

   [DeviceB] interface fortygige 1/0/1
   [DeviceB-FortyGigE1/0/1] duplex full
   [DeviceB-FortyGigE1/0/1] speed 40000
   [DeviceB-FortyGigE1/0/1] dldp enable
   [DeviceB-FortyGigE1/0/1] quit
   

   # Configure FortyGigE 1/0/2 to operate in full duplex mode and at 40000 Mbps, and enable DLDP on it.

   [DeviceB] interface 
   [DeviceB-FortyGigE1/0/2] duplex full
   [DeviceB-FortyGigE1/0/2] speed 40000
   [DeviceB-FortyGigE1/0/2] dldp enable
   [DeviceB-FortyGigE1/0/2] quit
   

   # Set the global port shutdown mode to hybrid.

   [DeviceB] dldp unidirectional-shutdown hybrid
   

# 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: Hybrid
 DLDP delaydown-timer value: 1s
 Number of enabled ports: 2

Interface FortyGigE1/0/1
 DLDP port state: Bidirectional
 DLDP port unidirectional-shutdown mode: None
 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 FortyGigE1/0/2
 DLDP port state: Bidirectional
 DLDP port unidirectional-shutdown mode: None
 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 and FortyGigE 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
FortyGigE1/0/1 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
FortyGigE1/0/2 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 FortyGigE1/0/1 changed to down.
%Jan  4 07:16:06:730 2011 DeviceA IFNET/3/PHY_UPDOWN: Physical state on the interface  changed to down.
%Jan  4 07:16:06:736 2011 DeviceA IFNET/5/LINK_UPDOWN: Line protocol state on the interface FortyGigE1/0/1 changed to down.
%Jan  4 07:16:06:738 2011 DeviceA IFNET/5/LINK_UPDOWN: Line protocol state on the interface FortyGigE1/0/2 changed to down.
%Jan  4 07:16:07:152 2011 DeviceA DLDP/3/DLDP_LINK_UNIDIRECTIONAL: DLDP detected a unidirectional link on interface FortyGigE1/0/1. 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 FortyGigE1/0/2. DLDP automatically shut down the interface. Please manually bring up the interface.

The output shows that the port status and link status of both and FortyGigE 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 FortyGigE1/0/1
 DLDP port state: Inactive
 DLDP port unidirectional-shutdown mode: None
 Number of the port's neighbors: 0 (Maximum number ever detected: 1)
Interface FortyGigE1/0/2
 DLDP port state: Inactive
 DLDP port unidirectional-shutdown mode: None
 Number of the port's neighbors: 0 (Maximum number ever detected: 1)

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

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

# Bring up FortyGigE 1/0/1.

<DeviceA> system-view
[DeviceA] interface fortygige 1/0/1
[DeviceA-FortyGigE1/0/1] undo shutdown

The following log information is displayed on Device A:

[DeviceA-]%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  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 FortyGigE 1/0/1 are now up and its DLDP neighbors are determined.

# Bring up FortyGigE 1/0/2.

[DeviceA-] quit
[DeviceA] interface fortygige 1/0/2
[DeviceA-FortyGigE1/0/2] undo shutdown

The following log information is displayed on Device A:

[DeviceA-FortyGigE1/0/2]%Jan  4 07:35:26:574 2011 DeviceA IFNET/3/PHY_UPDOWN: Physical state on the interface FortyGigE1/0/2 changed to up.
%Jan  4 07:35:57:562 2011 DeviceA DLDP/6/DLDP_NEIGHBOR_CONFIRMED: A neighbor was confirmed on interface FortyGigE1/0/2. 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 FortyGigE1/0/2.
%Jan  4 07:35:57:590 2011 DeviceA IFNET/5/LINK_UPDOWN: Line protocol state on the interface FortyGigE1/0/2 changed to up.
%Jan  4 07:35:57:609 2011 DeviceA STP/6/STP_DETECTED_TC: Instance 0's port  detected a topology change.

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