cpdt_port_down_status

Hello,

The link status is the information on the physical layer.

link status is 0  ---- link down

link status is 1  ---- link UP

link status is 3  ---- fault down (local fault or remote fault), detailed fault reason you may check at log.log files.

Link status 0 is PHY chip down which means physical down.

Link status 3 indicates that a fault is detected, but in this time the PHY status can be up, down or may also be an intermediate state from up to down.

There is an independent event and record in the register with cpdt_port_down_status.log files.

The display interface is only showing current status up & down, but the detail and history reason you need check in the cpdt_port_down_status.log.

(Example: the PHY status is up, and in this time port received the local fault & remote fault. And then the link status will become to 3. Later time the PHY status will become to down. That is mean “intermediate state from up to down”)

For more details about the fault, you can refer to RFC document 802.3-2008_section4.pdf  CL44-CL49.

I hope this helps.