unexpected link change on port

[Seb65]

Hello,

I have switch ports that goes from 1G to 10M-H

I have near FM radio antennas and 80Mhz emitters, can that be the cause ? I have firmware 1.5.4.

Code: Select all

 
Dec 31 22:36:42 Port: link state changed to 'up' (10M-H) on port 1

Dec 31 22:36:42 STP: msti 0 set port 1 to discarding

Dec 31 22:36:42 Port: link state changed to 'down' on port 1

Dec 31 22:36:42 switch[3980]: unexpected link change on port 1 (AF5) from 1G to 10M-H

Dec 31 22:36:45 Port: link state changed to 'up' (10M-H) on port 1

Dec 31 22:36:45 STP: msti 0 set port 1 to discarding

Dec 31 22:36:45 Port: link state changed to 'down' on port 1

Dec 31 22:37:04 Port: link state changed to 'up' (1G) on port 1

Dec 31 22:37:04 STP: msti 0 set port 1 to discarding

Dec 31 22:37:07 STP: msti 0 set port 1 to learning

Dec 31 22:37:07 STP: msti 0 set port 1 to forwarding
 

[sirhc]

Diagnostic practices 101

Could be FM noise
- Use better shielded cable and or run in conduit.

Could also be any of the following which I would try first:
Lose connection of one or both of the RJ45 connectors
- Unplug and blow out sockets, spring tang, and re insert connector making sure securely latched and add strain relief ties

Bad crimp end
- Replace ends (Turn POE OFF on port first or you could fry your switch)

Ground current flowing across your Ethernet cable
- Make sure tower grounds are BONDED to service grounds and even add 1 or 2 NEW ground rods to electrical service rods

Bad device or bad port in switch
- Try different port in switch and then swap out device on other end of cable

Bad cable, could be caused by kinking or stretch cable during installation
- You guessed it

[Seb65]

Hi Sirhc,

I use this cable (outside 5e FTP), this one is normally correct, what do you think ?

Bad crimp end
- Replace ends (Turn POE OFF on port first or you could fry your switch)

OK, I plan to replace the UBNT RJ45 connectors by that : TOUGHCable TC-GND
I also plan to add ferrite bead on the cable

Ground current flowing across your Ethernet cable
- Make sure tower grounds are BONDED to service grounds and even add 1 or 2 NEW ground rods to electrical service rods

Our equipment is well connected to the tower ground, I will see to add a second ground by connecting me to the existing ground ! Is this the right method ?

Bad device or bad port in switch
- Try different port in switch and then swap out device on other end of cable

Ok... The switch is brand new ! Port link is AUTO (Switch/AF5) no force speed on this equipements.