@agung7 

Could there be a loop on your network? In normal case MSTP means the switch will choose a port to disable to prevent the loop.

I don't know how you connect your system and how many switches you have, but it may be related to the loop or another switch stop working, so this switch try to change the port to active.

Tp-link has MSTP guide.

Hi @Somnus thanks for your reply!

Isn't if there is a loop on the switch device, the log will appear regularly? but in this case, the notification pops up unexpectedly.

Best regards,

Agung

Basically, up/down means the port is available for a cable/connection, but doesn't have one. Check the cable, or other computer. There are several potential sources of interface errors, including interface discards when there is insufficient bandwidth to support the traffic volume, misconfigured duplex and speed settings, excessive buffering on interfaces, misconfigured Ether Channels, and faulty cables or hardware.

The line protocol being down indicates a clocking or framing problem. Probable reasons for this are encapsulation and clock rate mismatches. Ethernet0 is administratively down, line protocol is down: This output indicates that a local interface has been manually shut down using the shutdown command.

A port on a computer can go up and down for a number of reasons. These include physical damage to the port, incorrect cable or port settings, or an outdated driver. It can also be due to a faulty connection, power outage, or other hardware or software issues. If the port is continually going up and down, it is a good idea to check all of these possibilities to identify the root cause of the issue.