Ethernet forced 1Gbps/FullDuplex Not Working

Hardware MikroTik hardware general
1

Hi there,
i’ve been troubleshooting a poor performance after a couple hops in my network. (on a single hop speedtests perform ok).
All those ports are set on Autonegotiation mode, and detects speed/duplex at 1Gbps/Full. So far so well…

After several tests, I realize I can get a better speed performance by setting ethernet ports from AutoNeg to 100Mbps/FullDuplex.
At the office, in my test lab, I couldn’t get ports working at forced Gigabit speed with or without flow control enabled and Gigabit devices at both ends. (Of course using cat6E wiring)
I tried to get forced Gbps speed on my RB’s against several devices (ToughSwitch, Huawei Optix RTN 620, Dell Latitude 3470, Ligowave RapidFire, AirFiber5x)
Even on a RB1036CCR-12G, I made a loop between ether1 and ether2, set both ports to 1Gbps/FullDuplex and they did not talk to each other !!

The routers models I tested were RB3011UiAS and CCR1016-12G running ROS 6.36.4 and ROS 6.37.4 one week later…

So my question is: ¿have you experinced similar issues? Is there a running bug on ROS about forced Gbps ether speed?

Jose Carrion

2

I would get a cable tester on there and ensure your connectors are all correct. Sounds like there is cable issue can you test with a short cable between the units that you 100% that is working.

3

All test made at my workbench were done with certified cables not longer than 2mts.

4

IEEE 802.3ab (1000BASE-T) says the use of auto-negotiation is mandatory for copper gigabit networks. Manually forced gigabit data rates are not supposed to work on any kind of equipment. I have no idea why those settings are still present in the configuration.

5

Thanks Andriys,
i’ve checked it and in fact autonegotiation is a must for copper gigabits networks.

http://standards.ieee.org/findstds/interps/IEEE802.3af-2003interp-6.pdf

Thread closed.