Guys, I own an RB751G-2HnD board, running RouterOS v5.24.
I’m trying to enable the gigabit speed desperately on ethernet ports without any success.
In webfig I see the options present, at : Speed 10Mbps 100Mbps 1Gbps
I switched speed to 1Gbps, applied, but nothing changed. Rebooted the box, even power-cycled, still only at 100Mbps.
I even tried to force the device at the other end of the cable to 1Gbps, 1Gbps-full-duplex instead of Autodetect but in that case no link could be established.
For some reason it looks like the routerboard RB751G-2HnD keeps sticking to nothing more than 100Mbps, I don’t know why.
Could anyone please help me, where to look for the problem? I’m pretty sure that the other device I wish to connect to has no problems regarding 1Gbps speed, as I successfully tested it with other gigabit switches, which cannot be said about RB751G-2HnD.
Try diffrerent cables to be sure it is not a cable fault and if there is still Gigabit link problem, write to support@mikrotik.com with attached supout.rif file.
Hmm… the PoE injector prevents usage of 1Gbps speed on the line. Tested without PoE, and it works at 1Gbps
The Power over Ethernet device seems to use the “vacant” pairs in the CAT5e/6 network cable of 100Mbps to supply the power. But a Gigabit setup there’s data on all 4 pairs, so this type of injector is not suitable.
Is there any Gigabit-compliant PoE injector, which is compatible with RB751G-2HnD board?
Guess what, it works perfectly with my RB751G-2HnD, using the injector only.
And !!! it’s possible to use both parts as PoE injectors ! Just use a DC female-to-female adapter on the PoE extractor side, and voila: you’ve got two gigabit PoE adapters compatible with Mikrotik.
For that price (5 GBP /pair), it’s a real bargain.
