Read https://forums.servethehome.com/ind...i-gigabit-1-2-5-5-10-switch.20851/post-274105 andHi,
I am currently having a somewhat disappointing experience:
I believe the problem is that the transceivers are 10Gbit on the switch side and n-gbit on the endpoint side. It's not TCP/IP but probably the switch itself that cant set the speeds properly. After all, it believes the connection is 10Gbit. I can get the same problems with a data center type switch like the ICX-6610 (The switch is capable of handling 4 x 40 gbE + 8 x 10GbE + 24 x 1GbE traffic, so 'buffers' or speed shouldnt be a problem)
The ICX 6610 is connected via SFP+ & an Ipolex transceiver for 10 GbE and a QSFP+ DAC for 40 GbE. The 10GbE connects to a Windows 10 box via a OWC AQ107 TB3 adapter. I can set the link speed explicitly to 1/2.5/5/10 GbE
- Windows 10GbE <-> ESXi 40 GbE gives 9.5 Gbit/s bi-directional
- Setting the TB3/AQ107 to 5GbE gives 5 Gbit/s from Win10 to ESXi and 1.5 Gbit/s reverse
- Setting the TB3/AQ107 to 2.5 GbE or even 1GbE gives 2.4Gbit/s & 900Mbit/s from Win 10 to ESXi but 80 Mbit/s reverse in both cases.
But if you test with restricted bandwidth (i.e.
iperf3 -b 2.5G
or iperf3 -b 1G
) - you'll get the 2.4 Gbit/s and 900 Mbit/s as expected. And reverse speeds improve to 1.9 Gbit/s and 800 Mbit/s respectivelyI've tested with Wiitek and it makes no difference. I believe if you want to mix speeds, you need a multi gigabit switch like the Netgear MS510TX or Buffalo BS-MP2012/2008 - or then you need TB3 adapters everywhere you want the full 10gbit/s speeds