Connected Network Interfaces Cannot Go Up

Publication Date:  2015-04-01 Views:  535 Downloads:  0
Issue Description
After network interfaces are connected, the interface indicator is off, the physical or protocol layer cannot go Up, or the physical and protocol layers cannot go Up.

Handling Process
1.  Use a running network cable to replace the existing one and connect interfaces again.

2.  Check whether the network interface configuration including the interface rate, duplex mode, and auto-negotiation on both devices are consistent.

GE0 is used as an example. Run the following command on both ends of GE0 to check the network interface configuration on the AR:

[Huawei-GigabitEthernet0/0/0]display this interface If the network interface configuration is consistent, the fault is rectified.

If the network interface configuration is inconsistent, perform the following steps.

GigabitEthernet0/0/0 current state : DOWN              
Line protocol current state : DOWN                     
Description:HUAWEI, AR Series, GigabitEthernet0/0/0 Interface      
Route Port,The Maximum Transmit Unit is 1500           
Internet Address is                    
IP Sending Frames' Format is PKTFMT_ETHNT_2, Hardware address is 5489-9875-4a0b              
Last physical up time   : -                            
Last physical down time : 2011-09-28 09:51:56          
Current system time: 2011-09-28 13:52:21               
Port Mode: COMMON COPPER                               
Speed : 1000,  Loopback: NONE                          
Duplex: FULL,  Negotiation: ENABLE                     
Mdi   : AUTO     
Last 300 seconds input rate 0 bits/sec, 0 packets/sec  
Last 300 seconds output rate 0 bits/sec, 0 packets/sec 
Input peak rate 0 bits/sec,Record time: -              
Output peak rate 0 bits/sec,Record time: -             
Input:  0 packets, 0 bytes                             
  Unicast:                  0,  Multicast:                   0       
  Broadcast:                0,  Jumbo:                       0            
  Discard:                  0,  Total Error:                 0        
  CRC:                      0,  Giants:                      0      
  Jabbers:                  0,  Throttles:                   0          
  Runts:                    0,  Alignments:                  0              
  Symbols:                  0,  Ignoreds:                    0            
  Frames:                   0                          
Output:  0 packets, 0 bytes                            
  Unicast:                  0,  Multicast:                   0          
  Broadcast:                0,  Jumbo:                       0          
  Discard:                  0,  Total Error:                 0     
  Collisions:               0,  ExcessiveCollisions:         0         
  Late Collisions:          0,  Deferreds:                   0        
  Buffers Purged:           0                          
    Input bandwidth utilization threshold : 100.00%    
    Output bandwidth utilization threshold: 100.00%    
    Input bandwidth utilization  :    0%               
Output bandwidth utilization :    0%

3.  Contact the carrier to detect the line.

4.  Check whether the RJ45 interface connected to the network interface of the AR is an Ethernet interface. If not, connect the network cable to the Ethernet interface.

The RJ45 interface is a universal interface. You can define pins according to your needs. Some needs are even defined as the power module and ground. During network interface connection, ensure that the Ethernet interface connects to the network cable. The interface may be damaged if a non-Ethernet interface connects to the network cable. After the network cable is connected, run the following cable to detect the cable connected to the Ethernet interface:


When the following information is displayed, locate the fault according to Table 1 and the following information.

Warning: The command will stop service for a while, continue [Y/N]?y                         
Sep 28 2011 13:57:54+00:00 Huawei %%01IFPDT/4/VCT(l)[13]:The user choose YES when there is a selection about whether to run VCT.   
Sep 28 2011 13:57:57+00:00 Huawei %%01IFPDT/4/IF_STATE(l)[14]:Interface GigabitEthernet0/0/0 has turned into DOWN state.           
Sep 28 2011 13:57:57+00:00 Huawei %%01IFNET/4/LINK_STATE(l)[15]:The line protocol IP on the interface GigabitEthernet0/0/0 has enter
ed the DOWN state.
Pair A length: 0 meter(s)                              
Pair B length: 0 meter(s)                              
Pair C length: 0 meter(s)                              
Pair D length: 0 meter(s)                              
Pair A state: Ok 
Pair B state: Ok 
Pair C state: Ok 

Pair D state: OkTable 1 Description of the virtual-cable-test command output 

Performing the preceding operations can solve most problems of the network interface not in Up state.

Root Cause
The network cable is faulty.
The network configuration is incorrect.
The carrier line is faulty.
The connected RJ45 interface is a non-Ethernet interface.