This section describes the troubleshooting flowchart and provides a step-by-step troubleshooting procedure for the fault that an Eth-Trunk interface cannot forward traffic.
1.Common Causes
After an Eth-Trunk interface is configured, it cannot forward traffic.
This fault is commonly caused by one of the following:
l Eth-Trunk member interfaces are faulty.
l Configurations of Eth-Trunk member interfaces on the two ends are inconsistent.
l The number of Up Eth-Trunk member interfaces is smaller than the lower threshold.
l Negotiation between member interfaces of the Eth-Trunk interface in static LACP mode fails.
2.Troubleshooting Flowchart
On the network shown in Figure 1-1, the Eth-Trunk interface cannot forward traffic.
Figure 1-1 Eth-Trunk network diagram
The troubleshooting roadmap is as follows:
l Check that Eth-Trunk member interfaces are working.
l Check information about Eth-Trunk member interfaces on both ends.
l Check that the number of Up member interfaces is greater than the configured lower threshold.
l Check that LACP negotiation succeeds if the Eth-Trunk interface is in static LACP mode.
Figure 1-2 shows the troubleshooting flowchart.
Figure 1-2 Troubleshooting flowchart
?.3.Troubleshooting Procedure
Saving the results of each troubleshooting step is recommended. If troubleshooting fails to correct the fault, you will have a record of your actions to provide Huawei technical support personnel.
Procedure
Step 1 Check that Eth-Trunk member interfaces work properly.
Run the display eth-trunk 1 command in any view to check the status of the Eth-Trunk interface.
[RouterA] display eth-trunk 1
Eth-Trunk1's state information is:
WorkingMode: NORMAL Hash
arithmetic:According to SA-XOR-DA
Least Active-linknumber: 1 Max Bandwidth-affected-linknumber: 8
Operate status: down Number Of Up
Port In Trunk: 0
--------------------------------------------------------------------------------
PortName
Status Weight
Ethernet2/0/1 Down
1
Ethernet2/0/2 Down
1
Ethernet2/0/3 Down
1
l If a member interface is Down, check the following items on the interface.
|
Check Item |
Method |
|
Whether the interface was manually shut down |
Run the interface interface-type interface-number command in the system view to enter the interface view, and then run the display this command to check the interface status. If the interface was shut down by using the shutdown command, run the undo shutdown command in the interface view. |
|
Whether the link fails |
Replace the cable between RouterA and RouterB. NOTE If RouterA connects to RouterB using a twisted pair, select a new twisted pair with a proper transmission distance according to the actual distance between RouterA and RouterB. |
|
Whether the interface fails |
Configure other idle interfaces as member interfaces of the Eth-Trunk. |
If the interface remains in the Down state, go to Step 5.
l If the member interface is Up, verify that each cable is correctly connected to interfaces. If the fault persists, go to Step 2.
Step 2 Check information about Eth-Trunk member interfaces on both ends.
Check information about member interfaces of the Eth-Trunk interface on Router A and Router B.
[RouterA] display eth-trunk 1
Eth-Trunk1's state information is:
WorkingMode: NORMAL Hash
arithmetic: According to SA-XOR-DA
Least Active-linknumber: 1 Max Bandwidth-affected-linknumber: 8
Operate status: up Number
Of Up Port In Trunk: 3
--------------------------------------------------------------------------------
PortName
Status Weight
Ethernet2/0/1
up 1
Ethernet2/0/2
up 1
Ethernet2/0/3
up 1
[RouterB] display eth-trunk 1
Eth-Trunk1's state information is:
WorkingMode: NORMAL Hash
arithmetic: According to SA-XOR-DA
Least Active-linknumber: 4 Max Bandwidth-affected-linknumber: 8
Operate status: up Number
Of Up Port In Trunk: 2
--------------------------------------------------------------------------------
PortName Status
Weight
Ethernet2/0/1 up 1
Ethernet2/0/2 up 1
l Check information about member interfaces of the Eth-Trunk interface on Router B.
l If the number of member interfaces of the Eth-Trunk interface on Router A differs from the number on Router B, add the required physical interfaces to the Eth-Trunk interface.
l If the number of member interfaces of the Eth-Trunk interface on Router A is the same as the number on Router B, go to Step 3.
Step 3 Check whether the Eth-Trunk interface is configured with a lower threshold of Up member interfaces.
Run the display eth-trunk 1 command on Router A and Router B to view the configuration of the Eth-Trunk interface.
[RouterA] display eth-trunk 1
Eth-Trunk1's state information is:
WorkingMode: NORMAL Hash
arithmetic: According to SA-XOR-DA
Least Active-linknumber: 4 Max Bandwidth-affected-linknumber: 8
Operate status: down Number Of
Up Port In Trunk: 8
--------------------------------------------------------------------------------
PortName
Status Weight
Ethernet2/0/1
up 1
Ethernet2/0/2
up 1
Ethernet2/0/3
up 1
The preceding command output shows that the lower threshold of Up member interfaces of the Eth-Trunk interface has been set to 4. However, the number of Up member interfaces of the Eth-Trunk interface is actually 3, which causes the Eth-Trunk interface to go Down.
l If the Eth-Trunk interface is configured with a lower threshold of Up member interfaces and this threshold is greater than the actual number of Up member interfaces, set the lower threshold to a smaller value.
l If the Eth-Trunk interface is not configured with a lower threshold of Up member interfaces, go to Step 4.
Step 4 Check whether Eth-Trunk interfaces work in static LACP mode.
Run the display eth-trunk 1 command on Router A and Router B to view the configuration of the Eth-Trunk interface.
[RouterA] display eth-trunk 1
Eth-Trunk1's state information is:
Local:
LAG ID:
1
WorkingMode: STATIC
Preempt Delay: Disabled Hash arithmetic: According to
SA-XOR-DA
System Priority: 32768 System ID: 0018-826f-fc7a
Least Active-linknumber: 1 Max Active-linknumber: 8
Operate status: down Number Of
Up Port In Trunk: 0
--------------------------------------------------------------------------------
ActorPortName Status PortType PortPri PortNo
PortKey PortState Weight
Ethernet2/0/1 Unselect 100M
32768 264 305
11100010 1
Ethernet2/0/2 Unselect 100M
32768 265 305
11100010 1
Ethernet2/0/3 Unselect 100M
32768 266 305
11100011 1
Partner:
--------------------------------------------------------------------------------
ActorPortName SysPri
SystemID PortPri PortNo
PortKey PortState
Ethernet2/0/1 0 0000-0000-0000
0 0
0 11100011
Ethernet2/0/2 0 0000-0000-0000
0 0
0 11100011
Ethernet2/0/3 0 0000-0000-0000
0 0
0 11100011
l If the Eth-Trunk interface is configured to work in static LACP mode and no physical interface is selected, LACP negotiation was unsuccessful. Possible causes for unsuccessful LACP negotiation are as follows:
− Member interfaces fail, causing timeout of LACP protocol packets.
To correct this problem, connect the cable to another idle interface and add the interface to the Eth-Trunk.
− The Eth-Trunk interface on one end is configured to work in static LACP mode, but the Eth-Trunk interface on the other end is not.
To correct this problem, make the configurations of the two ends of the Eth-Trunk link consistent.
After the configurations are corrected and LACP negotiation succeeds, the output of the display eth-trunk 1 command is as follows:
[RouterB] display eth-trunk 1
Eth-Trunk1's state information is:
Local:
LAG ID:
1
WorkingMode: STATIC
Preempt Delay: Disabled Hash arithmetic: According to
SA-XOR-DA
System Priority: 32768 System ID: 0018-826f-fc7a
Least Active-linknumber: 1 Max Active-linknumber: 8
Operate status: up Number
Of Up Port In Trunk: 3
--------------------------------------------------------------------------------
ActorPortName Status PortType PortPri PortNo
PortKey PortState Weight
Ethernet2/0/1 Selected 100M
32768 264 305
11111100 1
Ethernet2/0/2 Selected 100M
32768 265 305
11111100 1
Ethernet2/0/3 Selected 100M
32768 266 305
11111100 1
Partner:
--------------------------------------------------------------------------------
ActorPortName SysPri
SystemID PortPri PortNo
PortKey PortState
Ethernet2/0/1 32768 0018-823c-c473 32768
2056 305 11111100
Ethernet2/0/2 32768 0018-823c-c473 32768
2057 305 11111100
Ethernet2/0/3 32768 0018-823c-c473 32768
2058 305 11111100
If LACP negotiation fails after the configurations are corrected, go to Step 5.
l If the Eth-Trunk interface is not configured to work in static LACP mode, go to Step 5.
Step 5 Collect the following information and contact technical support personnel.
l Results of the preceding troubleshooting procedure
l Configuration files, log files, and alarm files of the devices
----End
