I have 1Gb cable service and want to upgrade my RB750 to a RB4011 and want to use the SFP+ port with S+RJ10 SFP connected to the Arris S33 modem 2.5Gb port. But it seems that there is conflicting information that it may not work in auto negotiation mode .

So to get it to work if the interface does not....
1) I could run a multi gig switch between them?
2) Force the rate of the interface to 2.5G?

1) If this is with the WAN (NOT the local addresses) IP, then you can't use a switch between them.

2) I had a similar issue with some SFP+ modules on a CRS305 switch, and the fix was to simply force the 2.5Gb mode. Also, considering that the RB4011 only has one SFP+ port, I think it would be a bad deal to use the router if you wanted >1Gb speeds to a single device because the only interface capable of it is being used.

If you use a dumb switch, it will work in between a router and a cable modem, but it becomes added failure point and adds cost.

I have doing more hunting and it does look like it will work if I force the negotiation mode to 2.5Gb fullduplex. Since my net work is 1Gb and I am using a Hex RB750 and a RB260GS, the switching interface will be the same with the RB4011 and will just be one unit. Also, if I load balance it between the two switches, it will be faster and moving the data between the 3 interfaces then the Hex RB750 and RB260GS.

The RB4011 is nice and is more then I need, but I would like to see them come out with a updated version of the Hex with a 10Gb SFP port and 5 10Gb ports, they could call it the Hex S+.

I wish mikrotik does a 4011 variant: by removing the switch chips ( at least on or even both)

I wish mikrotik does a 4011 variant: by removing the switch chips ( at least on or even both)

Yea, but at least you can put them in bridge mode and make the ports independent of each other. Also in 6.47.9, you can force the SFP+ to the interface mode you need to connect to.

If I had the possibility and could afford a 2.5Gbps Internet connection then I would probably use a CRS305+RB4011 or CRS326+RB4011

If I had the possibility and could afford a 2.5Gbps Internet connection then I would probably use a CRS305+RB4011 or CRS326+RB4011

The SFP+ port will interface with 2.5Gb connection directly through a copper or fiber module, so you do not need a switch between the wan and router for it to work. That is how I have my setup, Modem to Router SFP+.

I have 1.2Gb connection, but two of my buddies have 10Gb fiber connections in Japan and Korea. Both pay around 50$ US a month, so I can only wish to have that speed at that price.

My provider actually offers 1.2Gbps, but only with 30-40Mbps of upload, so it's quite worthless.