No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search

Reminder

To have a better experience, please upgrade your IE browser.

upgrade

Troubleshooting Switch Port and Interface Problems

Rate and give feedback:
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Troubleshooting Switch Port and Interface Problems

Troubleshooting Switch Port and Interface Problems

Introduction

This document describes how to locate the fault that an interface is in the physically down state and how to restore an interface in this state.

Interface Physically Down Overview

Ethernet interfaces are physical interfaces provided for operation and configuration. They are mainly used to receive and send data. Keeping interfaces in Up state is the most basic condition for normal operation of devices.

An interface in Down state cannot receive and send packets, and its indicator is off. A log message similar to the following is generated on the device:

IFPDT/4/IF_STATE(l)[3]:Interface GigabitEthernet0/0/12 has turned into DOWN state. 

To check the current physical status of an interface, run the display interface command. In the command output, the current state field indicates the physical status of an interface.

<HUAWEI> display interface gigabitethernet 0/0/12
GigabitEthernet0/0/12 current state : Administratively DOWN
Line protocol current state : DOWN
Description:
Switch Port, Link-type : access(negotiated),
PVID :1, TPID : 8100(Hex), The Maximum Frame Length is 9216
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 000b-0974-a475 
Last physical up time: 2013-08-10 21:09:51 
Last physical down time : 2013-08-10 21:10:51
Current system time: 2013-08-10 21:15:06
Port Mode: COMMON FIBER
Speed : 1000,Loopback: NONE
Duplex: FULL,Negotiation: ENABLE
Mdi: -,Flow-control: DISABLE
Last 300 seconds input rate 96 bits/sec, 0 packets/sec
Last 300 seconds output rate 96 bits/sec, 0 packets/sec
Input peak rate 15184 bits/sec, Record time: 2013-08-10 17:45:05
Output peak rate 15184 bits/sec, Record time: 2013-08-10 17:45:05

The current physical status of GE0/0/12 is Administratively DOWN, indicating that the shutdown command exists on the interface. The interface Down event is caused by the incorrect configuration. You need to run the undo shutdown command in the corresponding interface view.

NOTE:
  • For a Layer 2 physical interface: If its physical status indicated by the current state field displays Up, its protocol status indicated by the Line protocol current state field displays Up. For example, if a Layer 2 physical interface is connected correctly and its attribute configuration is correct, its physical status and protocol status are both Up.
  • For a Layer 3 physical interface: Its protocol status indicated by the Line protocol current state field displays Up only when its physical status indicated by the current state field displays Up and its protocol negotiation succeeds. For example, if a Layer 3 physical interface is connected correctly, its attribute configuration is correct, and it is not configured with an IP address, its physical status and protocol status are Up and Down respectively.

Interface Physically Down Causes and Recovery

Major causes of the interface physically Down event include hardware and software failures.

Hardware failures: include hardware failures of the local and peer devices, such as failures of cards, interfaces, optical modules, fibers, and network cables.

Software failures: include inconsistent configurations of the local and peer devices, such as the interface negotiation mode, rate, and duplex configuration.

The following figure shows the possible causes of the interface physically Down event.

Operator--Human Factors

Cause Description

When an interface changes from Up to physically Down, check whether improper operations are performed recently. For example, check whether cables are incorrectly removed and installed, accidental touch on the device causes loose cable connections, or misoperations are performed using commands on the device.

Troubleshooting Procedure

In any view of the interconnected two devices, run the display interface interface-type interface-number command to check the current running status and statistics of the specified interface.

<HUAWEI> display interface gigabitethernet 0/0/12
GigabitEthernet0/0/12 current state : DOWN//Current physical status of the interface
Line protocol current state : DOWN
Description:
Switch Port, Link-type : access(negotiated),
PVID :1, TPID : 8100(Hex), The Maximum Frame Length is 9216
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 000b-0974-a475 
Last physical up time: 2013-08-10 21:09:51 
Last physical down time : 2013-08-10 21:10:51
Current system time: 2013-08-10 21:15:06
Port Mode: COMMON FIBER//Working mode of the interface. COMMON COPPER indicates that the interface works as an electrical interface.
COMMON FIBER indicates that the interface works as an optical interface.
Speed : 1000,Loopback: NONE//The rates, loopback status, and link status on two ends must be consistent.
Duplex: FULL,Negotiation: ENABLE//The duplex mode and auto-negotiation status of the interfaces
on both ends of the link must be consistent.

Recovery Measure

  • In the command output, if the current state field displays Administratively down, the interface has been manually shut down. You need to run the undo shutdown command on the interface.
  • If the current state field displays Down, check whether interfaces on both ends of the link have the same rate, duplex mode, and auto-negotiation mode.

    a. If the Negotiation field displays ENABLE, the interface works in auto-negotiation mode and the rate and duplex mode are negotiated by interfaces on both ends of the link. If the two interfaces have different rates or duplex modes, run the restart command to restart the interfaces so that they can negotiate the rate or duplex mode again. If the negotiation fails, run the undo negotiation auto command to enable the interfaces to work in non-auto-negotiation mode. For the rate and duplex mode configurations, see the following situation.

    b. If the Negotiation field displays DISABLE, the interface works in non-auto-negotiation mode. You can run the speed { 10 | 100 | 1000 } and duplex { full | half } commands in the interface view to ensure that the rates and duplex modes of interfaces on both ends of the link are the same.

  • If the current state field displays ERROR DOWN (down-cause), check whether the interface is shut down because of error events. You need to rectify the fault according to the down-cause field. The following table lists common values of the down-cause field.

    Value of the down-cause Field

    Scenario

    Recovery Measure

    as-not-ready

    When the device negotiates to the AS mode, its interface status becomes Down and then becomes Up after services in the service profiles have been delivered.

    Before taking recovery measures, you are advised to rectify service faults to prevent the interface from entering the ERROR DOWN state again.

    You can recover an interface from the ERROR DOWN state using either of the following measures:

    • Manual recovery

      Run the shutdown and undo shutdown commands or run the restart command in the interface view to restart the interface.

    • Automatic recovery

      Run the error-down auto-recovery cause down-cause interval interval-value command in the system view to enable an interface to automatically restore to Up state from the Error-Down state.

    auto-defend

    After the auto-defend action command is used to configure actions against attack sources, the interface that receives attack packets is shut down to prevent the device from attacks.

    bpdu-protection

    On an STP-enabled network, after BPDU protection is configured on edge interfaces of a switch, the switch sets the physical status of the edge interface that receives BPDUs to Down to block services on this interface if the switch is attacked by forged BPDUs.

    efm-remote-failure

    When the efm trigger error-down command associates a remote fault event with the current interface of a switch, the switch sets the protocol status of the interface to Down to interrupt all services on the interface if EFM detects the critical-event, dying-gasp, link-fault, or timeout fault event.

    efm-threshold-event

    When link monitoring is configured for an interface on a link, the link is considered unavailable if the number of errored frames, errored codes, or errored frame seconds detected by the interface reaches or exceeds the threshold within a specified period. You can associate an EFM crossing event with the current interface. The system then sets the administrative status of the interface to Down. In this manner, all services on the interface are interrupted.

    error-statistics

    When an Ethernet interface configured with a backup link receives error packets, faults such as service packet loss occur. To ensure nonstop service transmission, when the number of received error packets reaches the alarm threshold, the interface is shut down and services are switched to the backup link.

    runts-error-statistics

    An interface receives Runts error packets if the optical fiber, network cable, or optical module is removed and reinstalled, the shutdown or undo shutdown command is executed, or Runts packets are forwarded on the network. To avoid worse impact on the device or services, the device counts the number of Runts error packets received by an interface within 1 minute, and shuts down the interface if the number reaches the alarm threshold 5.

    link-flap

    Cable faults or active/standby switchovers will cause an interface to frequently alternate between Up and Down. You can configure link flapping protection on interfaces. When the switch receives an interface Up/Down message, it checks the number of interface flappings and interval. If the number of interface flappings within the specified period reaches the configured limit, the switch shuts down the interface.

    storm-control

    After the storm control action is configured as error-down on an interface, the interface is shut down when the average rate of received broadcast, multicast, and unknown unicast packets is larger than the specified limit within the interval for detecting storms.

    port-security

    When interface security is configured on a switch, the MAC addresses learned by the switch become secure dynamic MAC addresses. If the port-security protect-action command sets the security protection action to shutdown on an interface, the interface is shut down when the number of secure MAC addresses learned by the interface exceeds the upper limit or static MAC address flapping is detected after static MAC address detection is enabled.

    mac-address-flapping

    When MAC address flapping occurs on a user network because of loops, you can configure a loop prevention action for the switch to perform when MAC address flapping occurs. After the MAC address flapping action is configured on an interface, if the switch detects MAC address flapping on the interface, it sets the physical status of the interface to Down.

    transceiver-power-low

    When the optical power of an Ethernet optical interface configured with a backup link is reduced, faults such as packet loss occur. To ensure normal service operation, the interface is triggered to transit to the Error-Down state and services are switched immediately if the optical power is lower than the lower alarm threshold.

    data-integrity-error

    After the switch runs for a long time, the chip memory identifier has a data integrity error.

Device--Device Hardware Failures

Cause Description

When a card, an interface, or the peer device becomes faulty, the corresponding interface becomes physically Down. Therefore, check whether hardware failures exist.

Relevant Configuration

Run the display interface brief command in any view to check brief information about the status and configuration of all interfaces.

<HUAWEI> display interface brief
… …
Interface             PHY    Protocol InUti OutUti inErrors outErrors
GigabitEthernet0/0/1  down   down       0%     0%     0       0
GigabitEthernet0/0/2  down   down       0%     0%     0       0
GigabitEthernet0/0/3  down   down       0%     0%     0       0
GigabitEthernet0/0/4  down   down       0%     0%     0       0
GigabitEthernet0/0/5  down   down       0%     0%     0       0
GigabitEthernet0/0/6  down   down       0%     0%     0       0
  • If multiple interfaces change from Up to Down, cards of the local device or peer device may become faulty and the peer device status may change. For example, an active/standby switchover is performed on the peer device, the peer device is in sleeping state or restarted.
  • If a single interface changes from Up to Down, check whether any metal reeds in the two connected interfaces have sunk or shifted. If not, run the loopback internal command in the interface view to check whether hardware failures occur in the interface. If the interface status indicated by the current state field changes to Up after the loopback internal command is executed, the internal connection of the interface is normal and no hardware failure occurs. If the interface status is still Down, the internal connection of the interface is abnormal and a hardware failure occurs.
    <HUAWEI> system-view 
    [HUAWEI] interface gigabitethernet 0/0/1
    [HUAWEI-GigabitEthernet0/0/1] loopback internal
    [HUAWEI-GigabitEthernet0/0/1] display this interface 
    GigabitEthernet0/0/1 current state : UP 
    Line protocol current state : UP 
    … …

Recovery Measure

  • Multiple interfaces become physically Down.

    a. If multiple interfaces become physically Down and these interfaces belong to the same card and are connected to multiple normal peer devices, the card may be faulty. Run the reset slot slot-id command to reset the card. If the fault persists, replace this card.

    b. If multiple interfaces become physically Down and these interfaces connect the local device to the same peer device, the peer device may be faulty. You need to log in to the peer device to check whether the corresponding card is faulty. If so, reset or replace it. If an active/standby switchover is performed on the peer device, or the peer device is in sleeping state or restarted, it is a normal situation that these interfaces become physically Down. These interfaces will automatically return to the Up state after the peer device becomes stable. In this scenario, the interfaces will frequently alternate between Up and Down, causing a large number of the following Up/Down logs:

    Apr 15 2013 03:46:14-05:13 dgg62aslhw3i %%01IFNET/4/IF_STATE(l)[46]:Interface
    GigabitEthernet1/0/1 has turned into UP state.
    Apr 15 2013 03:46:10-05:13 dgg62aslhw3i %%01IFNET/4/IF_STATE(l)[47]:Interface
    GigabitEthernet1/0/1 has turned into DOWN state.
    Apr 15 2013 03:45:35-05:13 dgg62aslhw3i %%01IFNET/4/IF_STATE(l)[48]:Interface
    GigabitEthernet1/0/1 has turned into UP state.
    Apr 15 2013 03:45:31-05:13 dgg62aslhw3i %%01IFNET/4/IF_STATE(l)[49]:Interface 
    GigabitEthernet1/0/1 has turned into DOWN state.
    Apr 15 2013 03:42:10-05:13 dgg62aslhw3i %%01IFNET/4/IF_STATE(l)[50]:Interface
    GigabitEthernet1/0/1 has turned into UP state.

    If the peer device is frequently restarted, for example, an AP connected to a switch is frequently restarted, the interface that connects the switch to the AP becomes physically Down. You need to check the reason for the frequent AP restart and determine whether a network loop occurs, whether a large number of ARP broadcast packets exist, and whether a network attack occurs. If these problems exist, solve them to ensure that the interface becomes Up.

  • A single interface becomes physically Down

    If only a single interface becomes physically Down, check whether any metal reeds in the two connected interfaces have sunk or shifted. If one interface becomes faulty, use another idle interface to replace this interface.

Material--Connection Media Failures

Cause Description

Physical interfaces of switches include electrical and optical interfaces. Involved transmission media include RJ45 cables, optical modules, and fibers. When transmission media are aging or damaged or optical modules receive and send signals abnormally, interfaces become physically Down.

Relevant Configuration

Connection media failures of electrical interfaces

  1. Check whether cables are connected correctly.

    Ensure that interfaces on both ends are connected using the same network cable. If the two interfaces are connected through the optical distribution frame, ensure that the network cables are connected correctly. Ensure that the interfaces are connected correctly, and that the cable is firmly installed and intact.

  1. Check whether the cable specification and length comply with related standards.

    According to Ethernet cable standards, the network cable length cannot exceed 100 meters. A GE electrical interface working at 1000 Mbits cannot go Up when it uses a network cable of a category lower than Category 5. A network cable of a category higher than Category 5 is recommended for the connection between electrical interfaces.

  1. Check whether the status of line pairs in cables is normal.

    If any of the four line pairs in a cable is damaged, connected electrical interfaces cannot go Up. Use a cable tester or run the virtual-cable-test command in the interface view to check whether line pairs in cables are correctly connected.

    If the Pair state field displays Ok, line pairs are normal. If the Pair state field displays another state (Open or Short for example), replace the cable with another cable for a test.

    [HUAWEI] interface gigabitethernet 0/0/1
    [HUAWEI-GigabitEthernet0/0/1] virtual-cable-test 
    Warning: The command will stop service for a while, Continue?[Y/N] y 
    Info: This operation may take a few seconds. Please wait for a moment..........done. 
    Pair A length: 1meter(s) 
    Pair B length: 1meter(s) 
    Pair C length: 1meter(s) 
    Pair D length: 1meter(s) 
    Pair A state: Ok 
    Pair B state: Ok 
    Pair C state: Ok 
    Pair D state: Ok 

Connection media failures of optical interfaces

  1. Check whether the optical module of the interface is a Huawei-certified optical module.

    For the Huawei-certified optical modules, Huawei has added Huawei logo and identifier and changed the vendor information in the product elabel and optical module information into HUAWEI.

    When an uncertified optical module is installed into a switch, the switch reports an alarm. The alarm format is as follows:

    ENTITYTRAP/3/OPTICALINVALID:OID [oid] Optical Module is invalid.(Index=[INTEGER],
    EntityPhysicalIndex=[INTEGER], PhysicalName=\"[OCTET]\", EntityTrapFaultID=[INTEGER])
  1. Check whether the optical module is normal.

    Run the display transceiver interface command to check whether optical modules of interfaces on both ends are normal, including the receive power, transmit power, and current. Ensure that these values are in the normal range.

    <HUAWEI> display transceiver interface GigabitEthernet 2/0/3 verbose 
    ...
    Diagnostic information: Temperature (°C) :39
    Voltage(V):3.32 
    Bias Current(mA):6.91         //Current
    Bias High Threshold(mA):33.34
    Bias LowThreshold(mA):1.67 
    Current Rx Power(dBM):-4.59  //Receive power of the interface
    Default Rx Power High Threshold(dBM):0.00
    Default Rx Power LowThreshold(dBM):-16.99 
    Current Tx Power(dBM):-5.10 //Transmit power of the interface
    Default Tx Power High Threshold(dBM):0.00 
    Default Tx Power LowThreshold(dBM):-12.50 
    User Set Rx Power High Threshold(dBM) :0.00 
    User Set Rx Power Low Threshold(dBM):-16.99 
    User Set Tx Power High Threshold(dBM) :0.00 
    User Set Tx Power Low Threshold(dBM):-12.50

Recovery Measure

Connection media failures of electrical interfaces

If the cable of an electrical interface is faulty, you are advised to replace this cable.

Connection media failures of optical interfaces

  1. If a non-Huawei certified optical module is installed, replace it with a Huawei-certified optical module. Non-Huawei certified optical modules cannot ensure transmission reliability and may affect service stability. Huawei is not responsible for any problem caused by the use of non-Huawei certified optical modules and will not fix such problems.
  1. Run the display transceiver interface command to check the parameters of optical modules and whether these parameters are within the normal range according to the following table.

    Optical Module Attribute

    Normal Range

    Voltage (V)

    The value is not 0.

    Bias current (mA)

    The value is between Bias LowThreshold(mA) and Bias High Threshold(mA).

    Current Rx Power (dBM)

    The value is between Default Rx Power LowThreshold(dBM) and Default Rx Power LowThreshold(dBM).

    Current Tx Power (dBM)

    The value is between Default Tx Power LowThreshold(dBM) and Default Tx Power LowThreshold(dBM).

If the transmit power of an optical module is too low or too high, replace the optical module.

If the receive power of an optical module is too low or too high, use an optical power meter to test the optical power attenuation of each part of the link and repair abnormal parts. If the fault persists, replace the optical module or fiber to ensure that the transmission distance and fiber type of the optical module meet networking requirements.

Incorrect Connection Media Usage

Cause Description

When connecting two devices, check whether optical modules match optical interfaces, whether optical modules match fiber models, and whether optical modules and fibers are connected correctly. When an interface becomes physically Down, rectify the fault accordingly.

Troubleshooting Procedure

  1. Run the display device command in any view to check the device model and component information. If the device is a modular switch, you can focus on the corresponding card names.
    <HUAWEI> display device 
    S9303 Device status://Device model. The following Type field indicates a card name.
    Slot Sub  Type      Online   Power   Register   Status   Role 
    ------------------------------------------------------------
    1     -   LE0MX4UXA Present  PowerOn Registered  Normal  NA
    
    2     -   LE0MF48TA Present  PowerOn Registered  Normal  NA
    3     -   LE0MG24SA Present  PowerOn Registered  Normal  NA
    4     -   LE0DMCUA  Present  PowerOn Registered  Normal  Master
    PWR1  -   -         Present  PowerOn Registered  Abnormal NA 
    FAN1  -   -         Present  PowerOn Registered  Normal   NA 
  2. Use the hardware query tool to check whether the used optical module type matches the interface and whether the optical module matches the fiber model.
  3. Run the display transceiver interface command in any view of the two devices to check whether optical module parameters on the two devices are consistent.
    <HUAWEI> display transceiver interface GigabitEthernet 0/0/1 verbose 
    GigabitEthernet0/0/1 transceiver information: 
    ------------------------------------------------------------- 
    Common information: Transceiver Type:1000_BASE_SX_SFP //Optical module model
    Connector Type:LC 
    WWavelength(nm):850      //Optical module wavelength
    Transfer Distance(m):500(50um),300(62.5um)//Optical module transmission distance
    Digital Diagnostic Monitoring:YES 
    Vendor Name:HUAWEI 
    Vendor Part Number:02315204 
    Ordering Name: 
    ------------------------------------------------------------- 
    Manufacture information: 
    Manu. Serial Number:NSK1NNV 
    Manufacturing Date:2014-11-09 
    Vendor Name:HUAWEI 
    -------------------------------------------------------------
  4. Check whether fibers are connected correctly. An optical module provides a TX end and an RX end. When connecting two interfaces, you need to connect the TX and RX ends of one optical module to the RX and TX ends of the other optical module using two fibers.

  5. Check whether the interface is a combo interface. If so, check whether the combo interface is used correctly. That is, check whether the current working mode of the interface is consistent with the current connection.

    Combo interface GE1/0/1 corresponds to two interfaces on the device panel: combo optical interface and combo electrical interface. The two interfaces cannot work at the same time. To configure the attributes of the combo optical or electrical interface, enter the same interface view of GE1/0/1.

    Run the display interface command in any view to check whether the interface is a combo interface and whether its working mode is correct.

    <HUAWEI> display interface gigabitethernet 1/0/1 
    GigabitEthernet1/0/1 current state : DOWN 
    Line protocol current state : DOWN 
    Description:HUAWEI, Quidway Series, GigabitEthernet1/0/1 Interface
    ...
    Port Mode: COMBO AUTO //A combo interface supports three
    working modes. COMBO Auto: The combo interface automatically selects the working mode.
    FORCE FIBER: The combo interface is configured to work as an optical interface.
    FORCE COPPER: The combo interface is configured to work as an electrical interface.
    Current Work Mode: COPPER //If the Port Mode field displays COMBO AUTO, 
    the Current Work Mode field displays the automatically selected working mode.
    COPPER indicates the electrical interface mode. FIBER indicates the optical interface mode.
    Speed : 100, Loopback: NONE 

Recovery Measure

  1. 1. Ensure that the currently used optical module matches the optical interface and fiber according to the hardware query tool. If they do not match, replace the corresponding component.
  2. 2. If the current interface is a combo interface, ensure that its working mode meets the following requirements:
    • When the auto mode is specified, the system checks whether the combo optical interface has an optical module installed, and selects the interface working mode as follows. To specify the auto mode, run the combo-port auto command in the interface view. By default, a combo interface works in auto mode.

      a. When the combo electrical interface is not connected, the combo interface works as an optical interface if the combo optical interface has an optical module installed.

      b. When the combo electrical interface is connected using a network cable and the combo interface is Up, the combo interface works as an electrical interface even if the combo optical interface has an optical module installed. However, the combo interface works as an optical interface after the device restarts.

      When the combo electrical interface is connected using a network cable and the combo interface is Down, the combo interface works as an optical interface if the combo optical interface has an optical module installed.

      In summary, when the auto mode is specified and the combo optical interface has an optical module installed, the combo interface works as an optical interface after the device restarts.

    • When the working mode of the combo interface is the force mode, you can forcibly specify the working mode based on the type of the interface connecting the local and remote devices.

      If the local combo electrical interface is connected to a peer electrical interface, run the combo-port copper command in the interface view to configure the combo interface to work in copper mode.

If the local combo optical interface is connected to a peer optical interface, run the combo-port fiber command in the interface view to configure the combo interface to work in fiber mode.

In summary, after confirming that the transmission media (optical fibers or cables) are correct, check whether the working mode of the combo interface is correct. You can run the combo-port {copper | fiber } command to ensure that the working mode of the interface matches the connection media.

Environment--Environmental Factors

Cause Description

Switches can be used in various scenarios at any network layer. When a switch and its connection media become faulty because of environmental factors, interfaces of the switch may become physically Down.

Troubleshooting Procedure

  • Check the temperature and humidity in the equipment room.

    For S series switches, the operating temperature is in the range 0℃ to 45℃, the relative humidity is in the range 5% RH to 95% RH (non-condensing).

  • Check cable layout.

    Power cables and service cables must be deployed separately. Low-current lines must be separated from high-current lines to prevent interference. Check whether network cables are damaged and aged out because of high temperature or rack wear.

Recovery Measure

  • If the temperature in the equipment room cannot meet the requirement for a long time, you may need to repair or replace the air conditioning. If the relative humidity in the equipment room is high, you may need to install a dehumidifier. If the relative humidity in the equipment room is low, you may need to install a humidifier.
  • If low-current lines and high-current lines are not separated, deploy these lines again to ensure that they are separated. If network cables are damaged and aged out because of environmental factors, replace the cables.
Translation
Download
Updated: 2019-06-29

Document ID: EDOC1100088112

Views: 1658

Downloads: 40

Average rating:
This Document Applies to these Products
Related Documents
Related Version
Share
Previous Next