Someone need to kickstart CM4 carrier board with multi-port Ethernet. The CM4 can support 5 Gpbs throughput and having 4-port Ethernet will make a really cheap and nice home router [1].
back
2 comments
Check out https://pipci.jeffgeerling.com/boards_cm — there are a couple multi-port boards already in the works.
Also, if you go to the main page on that site, I have tested multiple multi-port PCIe cards, like a dual 2.5G card and a 4-port Intel i340, and all of them can be made to work without too much effort.
There are a few different things you can do with it, but in total, you'll be limited to about 3.2 (only through PCIe) to 4.2 Gbps (if also using the Pi's internal 1G ethernet) of internal bandwidth.
> you'll be limited to about 3.2 (only through PCIe) to 4.2 Gbps (if also using the Pi's internal 1G ethernet) of internal bandwidth.
Is that the total full duplex bandwidth available or just the "one way" bandwidth?
Full duplex as far as I can measure (in various scenarios). I'm still wrangling a couple PCIe switches that were giving me trouble previously, so I will definitely keep trying to get more than that!
It would be interesting to see a barebones ethernet switch board with some L2/L3 features (VLAN, LACP, etc.) on the switch chip in the data plane, interfaced to the CM4 as the brain and management plane, as something with more programmability than commercial lower-end switches (same price range as Mikrotik/Ubiquiti gear).
I wonder how programmable/open/capable low-cost ethernet switching chips are these days.
From the follow on of the provided Twitter link in Jeff's website and based on the latest status updates, it seems that the 4-port Ethernet CM4 carrier or Raspberry Router from Blinkinlabs is taking shape now [1].
It uses KSZ9897 switch and LAN7431 PCIe-to-Ethernet adapter from Microchip, and the former does supports VLAN and LACP [2]. The fact that the switch chip can supports up to 7-port Ethernet thus it is possible to make a version of Raspberry Router that can be used in company setting (Mikrotik's customers) in addition to home networks.
[1]https://mobile.twitter.com/cibomahto/status/1364520950763573...