Hi,
We have a situation where we have all the ports on a router MT 433 set to 100Mbit FD, autoneg OFF, but two connections to a particular downstream switch show in Winbox as being connected at 100Mbit HALF duplex. How can this be when we have set autoneg off on the router? The equipment the other end is not ours, but is allegedly set to 100Mbit FD autoneg off as well.
This mismatch seems to occur randomly after weeks/ months of working fine at FD with no chages. A disable/ enable cycle on the ports from Winbox brings them back to FD fine. The environment is an indoor data centre, short Cat 5 leads, nothing unusual.
Other ports on the same router to other equipment are not affected.
Any information much appreciated.
Hello,
I have the same problem on a large number of RB4xx and newer routerboards after every reboot/power-up connected to a Cisco 3500/3560 type switch on many sites/locations.
It has started to happen somewhere between v3.26 and 3.30 of RouterOS and the problem is still here.
Solution I found is either to downgrade to v3.26 or to disable/enable FD on the
routerboard’s ethernet interface (I wrote a script which does that at every start-up).
Other users on this forum also reported strange issues with ethernet ports.
Since hardware seems to work OK with older verions of RouterOS I suspect the root cause of this problem is either a bad ethernet driver or some other software bug which started to appear sometimes after version 3.26.