An interface on a WLAN device fails to go Up

8

The possible causes are as follows:
- The interface is manually shut down.
- The power cable is faulty or the optical fiber does not meet requirements.
- If the interface is a combo interface, the working mode may be incorrectly configured.
- The duplex modes, rates, and negotiation modes are different on the connected interfaces.
- The device hardware is faulty.

Perform the following operations to rectify the fault:
1. If the interface is manually shut down, run the undo shutdown command in the interface view to enable it.
2. If the interface is an electrical interface or a combo interface working in electrical mode, check whether the power cable is faulty and securely connected on the local and remote devices.
If the interface is an optical interface or a combo interface working in optical mode, check whether the type and length of the optical fiber, and the transmission distance supported by the optical module meet requirements.

3. If the interface is a combo interface, run the display this command to check whether the interface mode is correctly configured.
- Run the combo-port auto or combo-port fiber command to set a combo interface to the auto or optical mode.
- Run the combo-port auto or combo-port copper command to set a combo interface to the auto or electrical mode.

4. Run the display interface [ interface-type [ interface-number ] ] command to check the rate, duplex mode, and negotiation mode of the interface. In the command, interface-type and interface-number specify the interface type and number, respectively.

- Check the Negotiation field.
If ENABLE is displayed, the interface works in auto-negotiation mode.
If DISABLE is displayed, the interface works in non-auto-negotiation mode.
The two interfaces on the local and remote devices must work in the same negotiation mode (auto-negotiation or non-auto-negotiation mode). You can run the negotiation auto command in the interface view to configure an interface to work in auto-negotiation mode. If the fault persists, configure the interface to work in non-auto-negotiation mode, and forcibly set the same rate and duplex mode for the interconnected interfaces.

- Check the Speed field. If the rates of the interfaces on the local and remote devices are different, run the speed command in the interface view to set the same rate for the two interfaces.
- Check the Duplex field. If the duplex modes of the interfaces on the local and remote devices are different, run the duplex command in the interface view to set the same duplex mode for the two interfaces.
5. Perform a loopback test on the AC using an Ethernet cable to connect the interface to another interface.
If the interface can go Up, the WLAN is working properly. The remote device may be faulty. Contact the vendor of the remote device to rectify the fault.
- If an electrical interface or a combo interface working in electrical mode cannot go Up, change it to another interface. If an optical interface or a combo interface working in optical mode cannot go Up, replace the optical module.

Other related questions:
An electrical port of a WLAN device cannot go Up
1. After a 100M/1000M electrical port on a WLAN device is connected to a port on the peer device, configure the electrical port to work in auto-negotiation mode. 2. If the fault persists, check whether the port on the peer device works in auto-negotiation mode. 3. If the port still cannot go Up when a Huawei WLAN device is connected to a non-Huawei WLAN device, configure ports on both devices to work in forcible mode. 4. If the fault persists, perform a loopback test by connecting the electrical port to another port on the same card on the Huawei device using an Ethernet cable. - If the electrical port goes Up, the peer device may be faulty. Contact the vendor of the peer device to rectify the fault. - If the fault persists, connect the Ethernet cable to another port on the same card. If the electrical port still cannot go Up, the card is faulty. Contact Huawei technical support personnel to rectify the fault.

An interface on a WLAN device goes Up or Down frequently
The possible causes are as follows: - The power cable is faulty or the optical fiber does not meet requirements. - The duplex modes, rates, and negotiation modes are different on the connected interfaces. - The device hardware is faulty. Perform the following operations to rectify the fault: 1. If the interface is an electrical interface or a combo interface working in electrical mode, check whether the power cable is faulty and securely connected on the local and remote devices. If the interface is an optical interface or a combo interface working in optical mode, check whether the type and length of the optical fiber, and the transmission distance supported by the optical module meet requirements. 2. Run the display interface [ interface-type [ interface-number ] ] command to check the rate, duplex mode, and negotiation mode of the interface. In the command, interface-type and interface-number specify the interface type and number, respectively. - Check the Negotiation field. If ENABLE is displayed, the interface works in auto-negotiation mode. If DISABLE is displayed, the interface works in non-auto-negotiation mode. The two interfaces on the local and remote devices must work in the same negotiation mode (auto-negotiation or non-auto-negotiation mode). You can run the negotiation auto command in the interface view to configure an interface to work in auto-negotiation mode. If the fault persists, configure the interface to work in non-auto-negotiation mode, and forcibly set the same rate and duplex mode for the interconnected interfaces. - Check the Speed field. If the rates of the interfaces on the local and remote devices are different, run the speed command in the interface view to set the same rate for the two interfaces. - Check the Duplex field. If the duplex modes of the interfaces on the local and remote devices are different, run the duplex command in the interface view to set the same duplex mode for the two interfaces. 3. Perform a loopback test on the AC using an Ethernet cable to connect the interface to another interface. If the interface can go Up, the WLAN is working properly. The remote device may be faulty. Contact the vendor of the remote device to rectify the fault. - If an electrical interface or a combo interface working in electrical mode cannot go Up, change it to another interface. If an optical interface or a combo interface working in optical mode cannot go Up, replace the optical module.

Configuring access interfaces on WLAN devices
The following example describes how to configure an access interface on a WLAN device: An access interface can connect to a user host. [HUAWEI]vlan batch 2 //Create a VLAN. [HUAWEI]interface gigabitethernet0/0/1 [HUAWEI-GigabitEthernet0/0/1]port link-type access //Set the interface type to access. [HUAWEI-GigabitEthernet0/0/1]port default vlan 2 //Add the interface to VLAN 2. [HUAWEI-GigabitEthernet0/0/1]quit

Configuring a trunk interface on a WLAN device
The following example describes how to configure a trunk interface on an AC: A trunk interface connects an AC to a switch. [HUAWEI]vlan batch 2 3 //Create VLANs. [HUAWEI]interface gigabitethernet 0/0/1 [HUAWEI-GigabitEthernet0/0/1]port link-type trunk //Set the link type of the interface to trunk. The link type of the interface is hybrid by default. [HUAWEI-GigabitEthernet0/0/1]port trunk allow-pass vlan all //Allow packets from all VLANs to pass through. By default, the interface allows only packets from VLAN 1 to pass through. [HUAWEI-GigabitEthernet0/0/1]port trunk pvid vlan 2 //(Optional) Specify VLAN 2 as the default VLAN of the interface (default: VLAN 1).

If you have more questions, you can seek help from following ways:
To iKnow To Live Chat
Scroll to top