FAQ-It prompts error if change the working mode of MA5200G port to auto-negotiation from forced 100M full duplex

Publication Date:  2012-07-27 Views:  78 Downloads:  0
Issue Description
  Q: It prompts error if change the working mode of MA5200G port to auto-negotiation from forced 100M full duplex, as follows:

[MA5200G-Ethernet1/0/4]negotiation auto
 Port does not support this command OR 
 'undo loopback' is necessary for this command !

 

Alarm Information
No

Handling Process
A: Two possible factors may be responsible for such a problem:

1. Loopback configuration for interface: execute display interface command to check if the interface is configured with loopback, as shown in the following red part:
[MA5200G-Ethernet1/0/4]disp inter e 1/0/4
Ethernet1/0/4 current state: up
Line protocol current state: up
  Hardware is WAN-FastEthernet,
  Address is 00e0-fc5f-bb14
  Description: ban-dao-lan-wan-2
  The Maximum Transmit Unit is 1500 bytes, the BandWidth is 100000 Kbits
  Send-frame-type is Ethernet_II, loopback not set



2. Otherwise, it indicates that FE optical interface does not support auto-negotiation, so it cannot be configured to that.

 

Root Cause
No

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