Causes and how to clear a ETH_LOS alarm on a RTN910

ETH_LOS

Description

The ETH_LOS is an alarm indicating the loss of Ethernet port connection.


Attribute

Parameters

None.


Impact on the System

     When the ETH_LOS alarm occurs, the service at the alarmed port is interrupted.


Possible Causes

• Cause 1: The negotiation fails because the transmit port and receive port work in different modes.
• Cause 2: The cable or fiber is faulty.
• Cause 3: The local receive end is faulty.
• Cause 4: The remote transmit end is faulty.
  

• Cause 1: The negotiation fails because the transmit port and receive port work in different modes.
  
  • Check whether the transmit port and receive port work in the same mode.

    If...	Then...
    The transmit port and receive port work in different modes	Correctly set the working modes of the transmit port and receive port.
    The transmit port and receive port work in the same mode	Go to Cause 2.

    
    
    
• Cause 2: The cable or fiber is faulty.
  
  • Check the network cable or fiber jumper connected to the alarmed port.

    If...	Then...
    The network cable is loose or damaged	Connect the network cable properly or replace the damaged network cable.
    The connector of the fiber jumper is dirty	Clean the connector.
    The connector or fiber is damaged	Insert the connector properly or replace the damaged fiber jumper.
    The connection is normal	Go to Cause 3.

    
    
    
• Cause 3: The local receive end is faulty.
  
  • Check whether any fault occurs on the alarmed port.

    If...	Then...
    The equipment is faulty	Replace the alarmed board on the local.
    The equipment is normal	Go to Cause 4.

    
    
    
• Cause 4: The remote transmit end is faulty.
  
  • Check whether any fault occurs on the equipment interconnected with the alarmed port.
  • Rectify the fault.