Revisiting the Sabrent USB 2.5G Ethernet Adapter on Raspberry Pi 4b 8GB (It Works Now)

Original thread:

You may recall from there that @Darksky did a testing kernel for me to play with, pulling the version of the driver that ships compiled into the kernel and replacing it with the one at AUR (en) - r8125-dkms .

This worked at the time, on a Rev. 1.1 Raspberry Pi 4B (4 GB), but absolutely refused to work when an external USB NVME SSD was plugged in. The whole system locked up and crashed. @Darksky experienced the same issue.

I’ve got a Rev Raspberry Pi 4B Rev. 1.4 (8GB) now, installed in a DeskPi and booting off a 2.5" SATA SSD on some sort of board that’s included with the DeskPi. (The DeskPi includes boards to: move ports around, provide full sized HDMI, provide a USB-to-SATA link for SSDs, and some other stuff, and has its own power delivery system.)

tl;dr: Some combination of the updated Raspberry Pi 4b board revision, using a SATA SSD instead of an NVME (and a different bridge chip to connect the SATA disk to the USB 3 bus), and whatever the DeskPi’s power delivery system is, is allowing the Sabrent adapter to work now, using the testing kernel and kernel module @Darksky prepared.

I left it running overnight, and the system was doing just fine when I came back. I haven’t tested it more thoroughly than that, but this is further than I ever got before with it. There’s still an issue on reboot (see below).

Here’s what ethtool says about it. It seems to be auto-negotiating full duplex 2.5G without a problem.

Settings for enp1s0u2:
        Supported ports: [ MII ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
                                2500baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Supported FEC modes: Not reported
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
                                2500baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Advertised FEC modes: Not reported
        Link partner advertised link modes:  100baseT/Half 100baseT/Full
                                             1000baseT/Full
        Link partner advertised pause frame use: No
        Link partner advertised auto-negotiation: Yes
        Link partner advertised FEC modes: Not reported
        Speed: 2500Mb/s
        Duplex: Full
        Auto-negotiation: on
        Port: MII
        PHYAD: 32
        Transceiver: internal
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00007fff (32767)
                               drv probe link timer ifdown ifup rx_err tx_err tx_queued intr tx_done rx_status pktdata hw wol
        Link detected: yes

Known Issues:

  1. The Pi can’t see the USB adapter on reboot. The link and activity lights on the adapter are both frozen in the on position, like it’s stuck doing something. Unplugging the adapter from its USB port and plugging it back in fixes the problem, then it seems rock solid: at the very least, it doesn’t randomly freeze the system after staying on overnight.
  2. The upstream version of the driver in the AUR has updated to 2.15.x. I’m not sure if there might be something useful in the latest version, as far as addressing the reboot issue. I haven’t found a changelog yet.

Here’s what happens when it’s unplugged and plugged back in, according to dmesg:

[Sun Nov 21 14:41:33 2021] usb 1-1.4: USB disconnect, device number 3
[Sun Nov 21 14:41:50 2021] usb 2-2: USB disconnect, device number 3
[Sun Nov 21 14:41:55 2021] usb 2-2: new SuperSpeed Gen 1 USB device number 4 using xhci_hcd
[Sun Nov 21 14:41:55 2021] usb 2-2: New USB device found, idVendor=0bda, idProduct=8156, bcdDevice=30.00
[Sun Nov 21 14:41:55 2021] usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=6
[Sun Nov 21 14:41:55 2021] usb 2-2: Product: USB 10/100/1G/2.5G LAN
[Sun Nov 21 14:41:55 2021] usb 2-2: Manufacturer: Realtek
[Sun Nov 21 14:41:55 2021] usb 2-2: SerialNumber: 000000001
[Sun Nov 21 14:41:55 2021] usbcore: registered new interface driver cdc_ether
[Sun Nov 21 14:41:55 2021] usbcore: registered new interface driver cdc_ncm
[Sun Nov 21 14:41:55 2021] usbcore: registered new interface driver cdc_wdm
[Sun Nov 21 14:41:55 2021] usbcore: registered new interface driver cdc_mbim
[Sun Nov 21 14:41:55 2021] r8152: loading out-of-tree module taints kernel.
[Sun Nov 21 14:41:55 2021] usb 2-2: reset SuperSpeed Gen 1 USB device number 4 using xhci_hcd
[Sun Nov 21 14:41:56 2021] r8152 2-2:1.0 (unnamed net_device) (uninitialized): netif_napi_add() called with weight 256
[Sun Nov 21 14:41:56 2021] r8152 2-2:1.0 eth1: v2.14.0 (2020/09/24)
[Sun Nov 21 14:41:56 2021] r8152 2-2:1.0 eth1: This product is covered by one or more of the following patents:
                                        US6,570,884, US6,115,776, and US6,327,625.

[Sun Nov 21 14:41:56 2021] usbcore: registered new interface driver r8152
[Sun Nov 21 14:41:56 2021] r8152 2-2:1.0 enp1s0u2: renamed from eth1
[Sun Nov 21 14:42:00 2021] IPv6: ADDRCONF(NETDEV_CHANGE): enp1s0u2: link becomes ready
[Sun Nov 21 14:42:00 2021] r8152 2-2:1.0 enp1s0u2: carrier on

Question: Is there any way to automate resetting the device in software, so I don’t have to manually unplug it every time?

EDIT: Here’s lsusb output, on boot before unplugging it, and immediately after unplugging it and plugging it back in.

~]$ lsusb
Bus 002 Device 003: ID 0bda:8151 Realtek Semiconductor Corp. RTL8151 Adapteon Business Mobile Networks BV
Bus 002 Device 002: ID 174c:55aa ASMedia Technology Inc. ASM1051E SATA 6Gb/s bridge, ASM1053E SATA 6Gb/s bridge, ASM1153 SATA 3Gb/s bridge, ASM1153E SATA 6Gb/s bridge
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

~]$ lsusb
Bus 002 Device 004: ID 0bda:8156 Realtek Semiconductor Corp. USB 10/100/1G/2.5G LAN
Bus 002 Device 002: ID 174c:55aa ASMedia Technology Inc. ASM1051E SATA 6Gb/s bridge, ASM1053E SATA 6Gb/s bridge, ASM1153 SATA 3Gb/s bridge, ASM1153E SATA 6Gb/s bridge
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

So, it’s being improperly identified as an RTL8151 on boot. This seems similar to the issue here: [SOLVED] [RTL8151] Ethernet not working via multiport adapter

There’s a little bit of storage on device, that has drivers on it so you can enable the thing on Windows or a Mac. I’m guessing that is the root cause of the needs to be unplugged/re-plugged issue. There’s a proposed solution in the linked thread above involving udev rules, but I barely understand those at this point, so I’ll need to do some testing.

1 Like

Absolutely rock solid so far. I’ve not overclocked this Pi yet, so here’s some iperf3 results. Without an overclock, the test pegs one CPU, and uses about ¾ of another.

The server is a 10 gigabit Mac mini (Intel).

Notice that the upload-to-server results max out at about 1.8 Gbps, but downloading hits the theoretical max of the adapter (~2.25 Gbps).

~]$ iperf3 -c 10.0.4.135 -P 10
Connecting to host 10.0.4.135, port 5201
[  5] local 10.0.4.139 port 34388 connected to 10.0.4.135 port 5201
[  7] local 10.0.4.139 port 34390 connected to 10.0.4.135 port 5201
[  9] local 10.0.4.139 port 34392 connected to 10.0.4.135 port 5201
[ 11] local 10.0.4.139 port 34394 connected to 10.0.4.135 port 5201
[ 13] local 10.0.4.139 port 34396 connected to 10.0.4.135 port 5201
[ 15] local 10.0.4.139 port 34398 connected to 10.0.4.135 port 5201
[ 17] local 10.0.4.139 port 34400 connected to 10.0.4.135 port 5201
[ 19] local 10.0.4.139 port 34402 connected to 10.0.4.135 port 5201
[ 21] local 10.0.4.139 port 34404 connected to 10.0.4.135 port 5201
[ 23] local 10.0.4.139 port 34406 connected to 10.0.4.135 port 5201
[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec  41.9 MBytes   351 Mbits/sec    0    286 KBytes       
[  7]   0.00-1.00   sec  21.1 MBytes   177 Mbits/sec    0    144 KBytes       
[  9]   0.00-1.00   sec  21.5 MBytes   180 Mbits/sec    0    140 KBytes       
[ 11]   0.00-1.00   sec  21.0 MBytes   176 Mbits/sec    0    141 KBytes       
[ 13]   0.00-1.00   sec  21.5 MBytes   181 Mbits/sec    0    141 KBytes       
[ 15]   0.00-1.00   sec  21.0 MBytes   176 Mbits/sec    0    140 KBytes       
[ 17]   0.00-1.00   sec  20.6 MBytes   173 Mbits/sec    0    137 KBytes       
[ 19]   0.00-1.00   sec  20.9 MBytes   175 Mbits/sec    0    143 KBytes       
[ 21]   0.00-1.00   sec  21.4 MBytes   180 Mbits/sec    0    133 KBytes       
[ 23]   0.00-1.00   sec  21.0 MBytes   176 Mbits/sec    0    143 KBytes       
[SUM]   0.00-1.00   sec   232 MBytes  1.94 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   1.00-2.00   sec  37.7 MBytes   316 Mbits/sec    0    293 KBytes       
[  7]   1.00-2.00   sec  19.4 MBytes   163 Mbits/sec    0    144 KBytes       
[  9]   1.00-2.00   sec  19.3 MBytes   161 Mbits/sec    0    140 KBytes       
[ 11]   1.00-2.00   sec  19.3 MBytes   161 Mbits/sec    0    141 KBytes       
[ 13]   1.00-2.00   sec  19.3 MBytes   161 Mbits/sec    0    141 KBytes       
[ 15]   1.00-2.00   sec  19.3 MBytes   161 Mbits/sec    0    140 KBytes       
[ 17]   1.00-2.00   sec  19.5 MBytes   163 Mbits/sec    0    144 KBytes       
[ 19]   1.00-2.00   sec  19.5 MBytes   163 Mbits/sec    0    143 KBytes       
[ 21]   1.00-2.00   sec  19.5 MBytes   164 Mbits/sec    0    140 KBytes       
[ 23]   1.00-2.00   sec  19.3 MBytes   162 Mbits/sec    0    143 KBytes       
[SUM]   1.00-2.00   sec   212 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   2.00-3.00   sec  37.3 MBytes   313 Mbits/sec    0    318 KBytes       
[  7]   2.00-3.00   sec  19.4 MBytes   163 Mbits/sec    0    144 KBytes       
[  9]   2.00-3.00   sec  19.6 MBytes   164 Mbits/sec    0    140 KBytes       
[ 11]   2.00-3.00   sec  19.6 MBytes   164 Mbits/sec    0    141 KBytes       
[ 13]   2.00-3.00   sec  19.5 MBytes   163 Mbits/sec    0    147 KBytes       
[ 15]   2.00-3.00   sec  19.5 MBytes   163 Mbits/sec    0    147 KBytes       
[ 17]   2.00-3.00   sec  19.4 MBytes   163 Mbits/sec    0    144 KBytes       
[ 19]   2.00-3.00   sec  19.3 MBytes   162 Mbits/sec    0    143 KBytes       
[ 21]   2.00-3.00   sec  19.2 MBytes   161 Mbits/sec    0    148 KBytes       
[ 23]   2.00-3.00   sec  19.1 MBytes   160 Mbits/sec    0    143 KBytes       
[SUM]   2.00-3.00   sec   212 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   3.00-4.00   sec  37.2 MBytes   312 Mbits/sec    0    318 KBytes       
[  7]   3.00-4.00   sec  19.4 MBytes   163 Mbits/sec    0    144 KBytes       
[  9]   3.00-4.00   sec  19.3 MBytes   162 Mbits/sec    0    150 KBytes       
[ 11]   3.00-4.00   sec  19.1 MBytes   160 Mbits/sec    0    163 KBytes       
[ 13]   3.00-4.00   sec  19.0 MBytes   160 Mbits/sec    0    147 KBytes       
[ 15]   3.00-4.00   sec  19.4 MBytes   163 Mbits/sec    0    147 KBytes       
[ 17]   3.00-4.00   sec  19.0 MBytes   160 Mbits/sec    0    144 KBytes       
[ 19]   3.00-4.00   sec  19.1 MBytes   161 Mbits/sec    0    146 KBytes       
[ 21]   3.00-4.00   sec  19.5 MBytes   164 Mbits/sec    0    148 KBytes       
[ 23]   3.00-4.00   sec  19.5 MBytes   164 Mbits/sec    0    154 KBytes       
[SUM]   3.00-4.00   sec   210 MBytes  1.77 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   4.00-5.00   sec  38.5 MBytes   323 Mbits/sec    0    318 KBytes       
[  7]   4.00-5.00   sec  19.0 MBytes   160 Mbits/sec    0    144 KBytes       
[  9]   4.00-5.00   sec  19.0 MBytes   159 Mbits/sec    0    150 KBytes       
[ 11]   4.00-5.00   sec  19.5 MBytes   164 Mbits/sec    0    163 KBytes       
[ 13]   4.00-5.00   sec  19.4 MBytes   163 Mbits/sec    0    147 KBytes       
[ 15]   4.00-5.00   sec  19.0 MBytes   160 Mbits/sec    0    147 KBytes       
[ 17]   4.00-5.00   sec  19.4 MBytes   163 Mbits/sec    0    144 KBytes       
[ 19]   4.00-5.00   sec  19.0 MBytes   160 Mbits/sec    0    146 KBytes       
[ 21]   4.00-5.00   sec  18.8 MBytes   158 Mbits/sec    0    148 KBytes       
[ 23]   4.00-5.00   sec  19.0 MBytes   160 Mbits/sec    0    154 KBytes       
[SUM]   4.00-5.00   sec   211 MBytes  1.77 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   5.00-6.00   sec  35.2 MBytes   295 Mbits/sec    0    318 KBytes       
[  7]   5.00-6.00   sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[  9]   5.00-6.00   sec  18.2 MBytes   153 Mbits/sec    0    150 KBytes       
[ 11]   5.00-6.00   sec  34.6 MBytes   290 Mbits/sec    0    277 KBytes       
[ 13]   5.00-6.00   sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 15]   5.00-6.00   sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 17]   5.00-6.00   sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[ 19]   5.00-6.00   sec  18.3 MBytes   153 Mbits/sec    0    146 KBytes       
[ 21]   5.00-6.00   sec  18.0 MBytes   151 Mbits/sec    0    148 KBytes       
[ 23]   5.00-6.00   sec  17.9 MBytes   150 Mbits/sec    0    154 KBytes       
[SUM]   5.00-6.00   sec   214 MBytes  1.79 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   6.00-7.00   sec  33.6 MBytes   282 Mbits/sec    0    318 KBytes       
[  7]   6.00-7.00   sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[  9]   6.00-7.00   sec  17.6 MBytes   148 Mbits/sec    0    150 KBytes       
[ 11]   6.00-7.00   sec  34.5 MBytes   290 Mbits/sec    0    294 KBytes       
[ 13]   6.00-7.00   sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 15]   6.00-7.00   sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 17]   6.00-7.00   sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[ 19]   6.00-7.00   sec  17.5 MBytes   147 Mbits/sec    0    146 KBytes       
[ 21]   6.00-7.00   sec  17.9 MBytes   150 Mbits/sec    0    148 KBytes       
[ 23]   6.00-7.00   sec  17.9 MBytes   150 Mbits/sec    0    154 KBytes       
[SUM]   6.00-7.00   sec   211 MBytes  1.77 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   7.00-8.00   sec  35.2 MBytes   295 Mbits/sec    0    318 KBytes       
[  7]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    144 KBytes       
[  9]   7.00-8.00   sec  17.7 MBytes   149 Mbits/sec    0    150 KBytes       
[ 11]   7.00-8.00   sec  34.9 MBytes   293 Mbits/sec    0    307 KBytes       
[ 13]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    147 KBytes       
[ 15]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    147 KBytes       
[ 17]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    144 KBytes       
[ 19]   7.00-8.00   sec  17.9 MBytes   150 Mbits/sec    0    146 KBytes       
[ 21]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    148 KBytes       
[ 23]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    154 KBytes       
[SUM]   7.00-8.00   sec   211 MBytes  1.77 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   8.00-9.00   sec  29.8 MBytes   250 Mbits/sec    0    318 KBytes       
[  7]   8.00-9.00   sec  15.6 MBytes   131 Mbits/sec    0    174 KBytes       
[  9]   8.00-9.00   sec  26.9 MBytes   226 Mbits/sec    0    255 KBytes       
[ 11]   8.00-9.00   sec  33.4 MBytes   280 Mbits/sec    0    395 KBytes       
[ 13]   8.00-9.00   sec  16.0 MBytes   134 Mbits/sec    0    174 KBytes       
[ 15]   8.00-9.00   sec  15.5 MBytes   130 Mbits/sec    0    160 KBytes       
[ 17]   8.00-9.00   sec  15.6 MBytes   131 Mbits/sec    0    153 KBytes       
[ 19]   8.00-9.00   sec  15.5 MBytes   130 Mbits/sec    0    178 KBytes       
[ 21]   8.00-9.00   sec  15.2 MBytes   128 Mbits/sec    0    148 KBytes       
[ 23]   8.00-9.00   sec  27.2 MBytes   228 Mbits/sec    0    273 KBytes       
[SUM]   8.00-9.00   sec   211 MBytes  1.77 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   9.00-10.00  sec  29.4 MBytes   247 Mbits/sec    0    318 KBytes       
[  7]   9.00-10.00  sec  15.3 MBytes   128 Mbits/sec    0    174 KBytes       
[  9]   9.00-10.00  sec  30.2 MBytes   253 Mbits/sec    0    264 KBytes       
[ 11]   9.00-10.00  sec  31.6 MBytes   265 Mbits/sec    0    395 KBytes       
[ 13]   9.00-10.00  sec  14.9 MBytes   125 Mbits/sec    0    174 KBytes       
[ 15]   9.00-10.00  sec  15.3 MBytes   128 Mbits/sec    0    160 KBytes       
[ 17]   9.00-10.00  sec  15.2 MBytes   128 Mbits/sec    0    153 KBytes       
[ 19]   9.00-10.00  sec  15.2 MBytes   128 Mbits/sec    0    178 KBytes       
[ 21]   9.00-10.00  sec  15.2 MBytes   128 Mbits/sec    0    157 KBytes       
[ 23]   9.00-10.00  sec  30.1 MBytes   253 Mbits/sec    0    273 KBytes       
[SUM]   9.00-10.00  sec   213 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec   356 MBytes   298 Mbits/sec    0             sender
[  5]   0.00-10.00  sec   354 MBytes   297 Mbits/sec                  receiver
[  7]   0.00-10.00  sec   182 MBytes   153 Mbits/sec    0             sender
[  7]   0.00-10.00  sec   182 MBytes   152 Mbits/sec                  receiver
[  9]   0.00-10.00  sec   209 MBytes   175 Mbits/sec    0             sender
[  9]   0.00-10.00  sec   208 MBytes   174 Mbits/sec                  receiver
[ 11]   0.00-10.00  sec   267 MBytes   224 Mbits/sec    0             sender
[ 11]   0.00-10.00  sec   266 MBytes   223 Mbits/sec                  receiver
[ 13]   0.00-10.00  sec   183 MBytes   153 Mbits/sec    0             sender
[ 13]   0.00-10.00  sec   182 MBytes   153 Mbits/sec                  receiver
[ 15]   0.00-10.00  sec   182 MBytes   153 Mbits/sec    0             sender
[ 15]   0.00-10.00  sec   181 MBytes   152 Mbits/sec                  receiver
[ 17]   0.00-10.00  sec   182 MBytes   153 Mbits/sec    0             sender
[ 17]   0.00-10.00  sec   181 MBytes   152 Mbits/sec                  receiver
[ 19]   0.00-10.00  sec   182 MBytes   153 Mbits/sec    0             sender
[ 19]   0.00-10.00  sec   182 MBytes   152 Mbits/sec                  receiver
[ 21]   0.00-10.00  sec   182 MBytes   153 Mbits/sec    0             sender
[ 21]   0.00-10.00  sec   182 MBytes   152 Mbits/sec                  receiver
[ 23]   0.00-10.00  sec   208 MBytes   175 Mbits/sec    0             sender
[ 23]   0.00-10.00  sec   207 MBytes   174 Mbits/sec                  receiver
[SUM]   0.00-10.00  sec  2.08 GBytes  1.79 Gbits/sec    0             sender
[SUM]   0.00-10.00  sec  2.08 GBytes  1.78 Gbits/sec                  receiver

Now, a download-from-server test. This pegs two of the CPU cores.

~]$ iperf3 -c 10.0.4.135 -P 10 -R
Connecting to host 10.0.4.135, port 5201
Reverse mode, remote host 10.0.4.135 is sending
[  5] local 10.0.4.139 port 34410 connected to 10.0.4.135 port 5201
[  7] local 10.0.4.139 port 34412 connected to 10.0.4.135 port 5201
[  9] local 10.0.4.139 port 34414 connected to 10.0.4.135 port 5201
[ 11] local 10.0.4.139 port 34416 connected to 10.0.4.135 port 5201
[ 13] local 10.0.4.139 port 34418 connected to 10.0.4.135 port 5201
[ 15] local 10.0.4.139 port 34420 connected to 10.0.4.135 port 5201
[ 17] local 10.0.4.139 port 34422 connected to 10.0.4.135 port 5201
[ 19] local 10.0.4.139 port 34424 connected to 10.0.4.135 port 5201
[ 21] local 10.0.4.139 port 34426 connected to 10.0.4.135 port 5201
[ 23] local 10.0.4.139 port 34428 connected to 10.0.4.135 port 5201
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  27.5 MBytes   231 Mbits/sec                  
[  7]   0.00-1.00   sec  26.7 MBytes   224 Mbits/sec                  
[  9]   0.00-1.00   sec  27.5 MBytes   231 Mbits/sec                  
[ 11]   0.00-1.00   sec  26.7 MBytes   224 Mbits/sec                  
[ 13]   0.00-1.00   sec  29.2 MBytes   245 Mbits/sec                  
[ 15]   0.00-1.00   sec  20.0 MBytes   168 Mbits/sec                  
[ 17]   0.00-1.00   sec  26.8 MBytes   225 Mbits/sec                  
[ 19]   0.00-1.00   sec  27.2 MBytes   229 Mbits/sec                  
[ 21]   0.00-1.00   sec  27.7 MBytes   233 Mbits/sec                  
[ 23]   0.00-1.00   sec  26.3 MBytes   221 Mbits/sec                  
[SUM]   0.00-1.00   sec   266 MBytes  2.23 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   1.00-2.00   sec  30.3 MBytes   254 Mbits/sec                  
[  7]   1.00-2.00   sec  27.8 MBytes   233 Mbits/sec                  
[  9]   1.00-2.00   sec  30.7 MBytes   258 Mbits/sec                  
[ 11]   1.00-2.00   sec  29.4 MBytes   246 Mbits/sec                  
[ 13]   1.00-2.00   sec  28.1 MBytes   236 Mbits/sec                  
[ 15]   1.00-2.00   sec  18.8 MBytes   157 Mbits/sec                  
[ 17]   1.00-2.00   sec  19.1 MBytes   160 Mbits/sec                  
[ 19]   1.00-2.00   sec  28.9 MBytes   243 Mbits/sec                  
[ 21]   1.00-2.00   sec  26.0 MBytes   218 Mbits/sec                  
[ 23]   1.00-2.00   sec  28.4 MBytes   238 Mbits/sec                  
[SUM]   1.00-2.00   sec   268 MBytes  2.24 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   2.00-3.00   sec  28.7 MBytes   241 Mbits/sec                  
[  7]   2.00-3.00   sec  29.1 MBytes   244 Mbits/sec                  
[  9]   2.00-3.00   sec  28.1 MBytes   235 Mbits/sec                  
[ 11]   2.00-3.00   sec  29.3 MBytes   246 Mbits/sec                  
[ 13]   2.00-3.00   sec  27.3 MBytes   229 Mbits/sec                  
[ 15]   2.00-3.00   sec  27.3 MBytes   229 Mbits/sec                  
[ 17]   2.00-3.00   sec  26.8 MBytes   225 Mbits/sec                  
[ 19]   2.00-3.00   sec  28.9 MBytes   242 Mbits/sec                  
[ 21]   2.00-3.00   sec  25.2 MBytes   211 Mbits/sec                  
[ 23]   2.00-3.00   sec  17.6 MBytes   147 Mbits/sec                  
[SUM]   2.00-3.00   sec   268 MBytes  2.25 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   3.00-4.00   sec  26.1 MBytes   219 Mbits/sec                  
[  7]   3.00-4.00   sec  27.7 MBytes   232 Mbits/sec                  
[  9]   3.00-4.00   sec  27.1 MBytes   228 Mbits/sec                  
[ 11]   3.00-4.00   sec  28.1 MBytes   236 Mbits/sec                  
[ 13]   3.00-4.00   sec  26.6 MBytes   223 Mbits/sec                  
[ 15]   3.00-4.00   sec  27.7 MBytes   233 Mbits/sec                  
[ 17]   3.00-4.00   sec  26.2 MBytes   220 Mbits/sec                  
[ 19]   3.00-4.00   sec  25.7 MBytes   215 Mbits/sec                  
[ 21]   3.00-4.00   sec  24.6 MBytes   206 Mbits/sec                  
[ 23]   3.00-4.00   sec  25.7 MBytes   215 Mbits/sec                  
[SUM]   3.00-4.00   sec   266 MBytes  2.23 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   4.00-5.00   sec  27.3 MBytes   229 Mbits/sec                  
[  7]   4.00-5.00   sec  28.8 MBytes   242 Mbits/sec                  
[  9]   4.00-5.00   sec  26.7 MBytes   224 Mbits/sec                  
[ 11]   4.00-5.00   sec  27.7 MBytes   233 Mbits/sec                  
[ 13]   4.00-5.00   sec  26.9 MBytes   225 Mbits/sec                  
[ 15]   4.00-5.00   sec  28.9 MBytes   243 Mbits/sec                  
[ 17]   4.00-5.00   sec  25.1 MBytes   211 Mbits/sec                  
[ 19]   4.00-5.00   sec  24.7 MBytes   208 Mbits/sec                  
[ 21]   4.00-5.00   sec  25.4 MBytes   213 Mbits/sec                  
[ 23]   4.00-5.00   sec  24.2 MBytes   203 Mbits/sec                  
[SUM]   4.00-5.00   sec   266 MBytes  2.23 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   5.00-6.00   sec  28.6 MBytes   240 Mbits/sec                  
[  7]   5.00-6.00   sec  27.4 MBytes   230 Mbits/sec                  
[  9]   5.00-6.00   sec  27.9 MBytes   234 Mbits/sec                  
[ 11]   5.00-6.00   sec  19.6 MBytes   164 Mbits/sec                  
[ 13]   5.00-6.00   sec  27.5 MBytes   231 Mbits/sec                  
[ 15]   5.00-6.00   sec  29.8 MBytes   250 Mbits/sec                  
[ 17]   5.00-6.00   sec  25.5 MBytes   214 Mbits/sec                  
[ 19]   5.00-6.00   sec  27.8 MBytes   233 Mbits/sec                  
[ 21]   5.00-6.00   sec  24.7 MBytes   207 Mbits/sec                  
[ 23]   5.00-6.00   sec  26.0 MBytes   218 Mbits/sec                  
[SUM]   5.00-6.00   sec   265 MBytes  2.22 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   6.00-7.00   sec  28.9 MBytes   242 Mbits/sec                  
[  7]   6.00-7.00   sec  18.2 MBytes   153 Mbits/sec                  
[  9]   6.00-7.00   sec  28.8 MBytes   241 Mbits/sec                  
[ 11]   6.00-7.00   sec  28.5 MBytes   239 Mbits/sec                  
[ 13]   6.00-7.00   sec  28.2 MBytes   236 Mbits/sec                  
[ 15]   6.00-7.00   sec  28.1 MBytes   236 Mbits/sec                  
[ 17]   6.00-7.00   sec  26.7 MBytes   224 Mbits/sec                  
[ 19]   6.00-7.00   sec  27.5 MBytes   231 Mbits/sec                  
[ 21]   6.00-7.00   sec  27.8 MBytes   233 Mbits/sec                  
[ 23]   6.00-7.00   sec  25.2 MBytes   211 Mbits/sec                  
[SUM]   6.00-7.00   sec   268 MBytes  2.25 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   7.00-8.00   sec  28.9 MBytes   242 Mbits/sec                  
[  7]   7.00-8.00   sec  29.4 MBytes   247 Mbits/sec                  
[  9]   7.00-8.00   sec  19.0 MBytes   160 Mbits/sec                  
[ 11]   7.00-8.00   sec  29.5 MBytes   247 Mbits/sec                  
[ 13]   7.00-8.00   sec  26.2 MBytes   220 Mbits/sec                  
[ 15]   7.00-8.00   sec  27.4 MBytes   230 Mbits/sec                  
[ 17]   7.00-8.00   sec  28.1 MBytes   236 Mbits/sec                  
[ 19]   7.00-8.00   sec  26.4 MBytes   221 Mbits/sec                  
[ 21]   7.00-8.00   sec  26.2 MBytes   220 Mbits/sec                  
[ 23]   7.00-8.00   sec  25.3 MBytes   212 Mbits/sec                  
[SUM]   7.00-8.00   sec   266 MBytes  2.23 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   8.00-9.00   sec  28.8 MBytes   242 Mbits/sec                  
[  7]   8.00-9.00   sec  19.1 MBytes   160 Mbits/sec                  
[  9]   8.00-9.00   sec  30.3 MBytes   254 Mbits/sec                  
[ 11]   8.00-9.00   sec  28.2 MBytes   236 Mbits/sec                  
[ 13]   8.00-9.00   sec  30.8 MBytes   258 Mbits/sec                  
[ 15]   8.00-9.00   sec  28.6 MBytes   240 Mbits/sec                  
[ 17]   8.00-9.00   sec  28.9 MBytes   242 Mbits/sec                  
[ 19]   8.00-9.00   sec  28.0 MBytes   235 Mbits/sec                  
[ 21]   8.00-9.00   sec  17.4 MBytes   146 Mbits/sec                  
[ 23]   8.00-9.00   sec  27.4 MBytes   230 Mbits/sec                  
[SUM]   8.00-9.00   sec   267 MBytes  2.24 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   9.00-10.00  sec  26.8 MBytes   225 Mbits/sec                  
[  7]   9.00-10.00  sec  32.8 MBytes   275 Mbits/sec                  
[  9]   9.00-10.00  sec  28.8 MBytes   242 Mbits/sec                  
[ 11]   9.00-10.00  sec  23.1 MBytes   194 Mbits/sec                  
[ 13]   9.00-10.00  sec  29.4 MBytes   247 Mbits/sec                  
[ 15]   9.00-10.00  sec  27.4 MBytes   230 Mbits/sec                  
[ 17]   9.00-10.00  sec  27.8 MBytes   233 Mbits/sec                  
[ 19]   9.00-10.00  sec  29.2 MBytes   245 Mbits/sec                  
[ 21]   9.00-10.00  sec  11.4 MBytes  96.0 Mbits/sec                  
[ 23]   9.00-10.00  sec  27.5 MBytes   230 Mbits/sec                  
[SUM]   9.00-10.00  sec   264 MBytes  2.22 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-10.00  sec   282 MBytes   237 Mbits/sec                  sender
[  5]   0.00-10.00  sec   282 MBytes   237 Mbits/sec                  receiver
[  7]   0.00-10.00  sec   267 MBytes   224 Mbits/sec                  sender
[  7]   0.00-10.00  sec   267 MBytes   224 Mbits/sec                  receiver
[  9]   0.00-10.00  sec   275 MBytes   231 Mbits/sec                  sender
[  9]   0.00-10.00  sec   275 MBytes   231 Mbits/sec                  receiver
[ 11]   0.00-10.00  sec   270 MBytes   227 Mbits/sec                  sender
[ 11]   0.00-10.00  sec   270 MBytes   227 Mbits/sec                  receiver
[ 13]   0.00-10.00  sec   280 MBytes   235 Mbits/sec                  sender
[ 13]   0.00-10.00  sec   280 MBytes   235 Mbits/sec                  receiver
[ 15]   0.00-10.00  sec   264 MBytes   222 Mbits/sec                  sender
[ 15]   0.00-10.00  sec   264 MBytes   222 Mbits/sec                  receiver
[ 17]   0.00-10.00  sec   261 MBytes   219 Mbits/sec                  sender
[ 17]   0.00-10.00  sec   261 MBytes   219 Mbits/sec                  receiver
[ 19]   0.00-10.00  sec   274 MBytes   230 Mbits/sec                  sender
[ 19]   0.00-10.00  sec   274 MBytes   230 Mbits/sec                  receiver
[ 21]   0.00-10.00  sec   237 MBytes   198 Mbits/sec                  sender
[ 21]   0.00-10.00  sec   236 MBytes   198 Mbits/sec                  receiver
[ 23]   0.00-10.00  sec   254 MBytes   213 Mbits/sec                  sender
[ 23]   0.00-10.00  sec   253 MBytes   213 Mbits/sec                  receiver
[SUM]   0.00-10.00  sec  2.60 GBytes  2.24 Gbits/sec                  sender
[SUM]   0.00-10.00  sec  2.60 GBytes  2.23 Gbits/sec                  receiver

iperf Done.

I’ll post a separate reply once I overclock the Pi and re-run the tests.

Tested again, this time with overclock.
My overclock settings:

# Overclock
#overclock (ETA Prime @ https://www.youtube.com/watch?v=TwDbQ26_Mp8&t=398s )
over_voltage=6                                                                # Overvolt CPU
arm_freq_min=1000                                                             # Keep CPU from dropping below 1 Ghz
arm_freq=2000                  #working
core_freq=700                                                                 # Possibly may cause boot failure to have this enabled on Pi 4B
h264_freq=700
isp_freq=700
v3d_freq=700
hevc_freq=700
#gpu_freq=700 (not recommended for Pi 4B. See: https://www.raspberrypi.org/documentation/configuration/config-txt/overclocking.md)

Overall, I think this is a very impressive result. I might be able to squeeze more out if I messed with jumbo frames and VLANs, but I have no desire to do that. All I wanted was to double my upload and download speed internally on my LAN; goal achieved.

It’s also worth noting that both the base and overclocked results in this thread are being recorded while a USB boot drive is occupying the same USB 3/PCIe bus.

Uploading to server. CPU usage stays much, much lower (18-35 percent on two cores), but frequency never goes above 1GHz, either. I’m still seeing a maximum upload of 1.8 Gbps, but the system is under much less strain doing it.

~]$ iperf3 -c 10.0.4.135 -P 10
Connecting to host 10.0.4.135, port 5201
[  5] local 10.0.4.139 port 36576 connected to 10.0.4.135 port 5201
[  7] local 10.0.4.139 port 36578 connected to 10.0.4.135 port 5201
[  9] local 10.0.4.139 port 36580 connected to 10.0.4.135 port 5201
[ 11] local 10.0.4.139 port 36582 connected to 10.0.4.135 port 5201
[ 13] local 10.0.4.139 port 36584 connected to 10.0.4.135 port 5201
[ 15] local 10.0.4.139 port 36586 connected to 10.0.4.135 port 5201
[ 17] local 10.0.4.139 port 36588 connected to 10.0.4.135 port 5201
[ 19] local 10.0.4.139 port 36590 connected to 10.0.4.135 port 5201
[ 21] local 10.0.4.139 port 36592 connected to 10.0.4.135 port 5201
[ 23] local 10.0.4.139 port 36594 connected to 10.0.4.135 port 5201
[ ID] Interval           Transfer     Bitrate         Retr  Cwnd
[  5]   0.00-1.00   sec  22.1 MBytes   185 Mbits/sec    0    141 KBytes       
[  7]   0.00-1.00   sec  21.8 MBytes   183 Mbits/sec    0    124 KBytes       
[  9]   0.00-1.00   sec  21.5 MBytes   180 Mbits/sec    0    137 KBytes       
[ 11]   0.00-1.00   sec  21.8 MBytes   183 Mbits/sec    0    129 KBytes       
[ 13]   0.00-1.00   sec  21.5 MBytes   180 Mbits/sec    0    109 KBytes       
[ 15]   0.00-1.00   sec  21.6 MBytes   182 Mbits/sec    0    139 KBytes       
[ 17]   0.00-1.00   sec  21.5 MBytes   180 Mbits/sec    0    133 KBytes       
[ 19]   0.00-1.00   sec  21.6 MBytes   181 Mbits/sec    0    136 KBytes       
[ 21]   0.00-1.00   sec  21.3 MBytes   179 Mbits/sec    0    110 KBytes       
[ 23]   0.00-1.00   sec  21.4 MBytes   179 Mbits/sec    0    110 KBytes       
[SUM]   0.00-1.00   sec   216 MBytes  1.81 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   1.00-2.00   sec  21.1 MBytes   177 Mbits/sec    0    141 KBytes       
[  7]   1.00-2.00   sec  20.9 MBytes   175 Mbits/sec    0    124 KBytes       
[  9]   1.00-2.00   sec  21.2 MBytes   178 Mbits/sec    0    144 KBytes       
[ 11]   1.00-2.00   sec  21.0 MBytes   176 Mbits/sec    0    137 KBytes       
[ 13]   1.00-2.00   sec  21.1 MBytes   177 Mbits/sec    0    122 KBytes       
[ 15]   1.00-2.00   sec  20.9 MBytes   175 Mbits/sec    0    139 KBytes       
[ 17]   1.00-2.00   sec  20.9 MBytes   175 Mbits/sec    0    133 KBytes       
[ 19]   1.00-2.00   sec  21.2 MBytes   178 Mbits/sec    0    136 KBytes       
[ 21]   1.00-2.00   sec  21.1 MBytes   177 Mbits/sec    0    116 KBytes       
[ 23]   1.00-2.00   sec  21.1 MBytes   177 Mbits/sec    0    132 KBytes       
[SUM]   1.00-2.00   sec   210 MBytes  1.77 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   2.00-3.01   sec  21.3 MBytes   177 Mbits/sec    0    151 KBytes       
[  7]   2.00-3.01   sec  21.3 MBytes   177 Mbits/sec    0    124 KBytes       
[  9]   2.00-3.01   sec  20.6 MBytes   171 Mbits/sec    0    144 KBytes       
[ 11]   2.00-3.01   sec  21.3 MBytes   177 Mbits/sec    0    139 KBytes       
[ 13]   2.00-3.01   sec  21.4 MBytes   178 Mbits/sec    0    136 KBytes       
[ 15]   2.00-3.01   sec  20.5 MBytes   170 Mbits/sec    0    139 KBytes       
[ 17]   2.00-3.01   sec  20.5 MBytes   170 Mbits/sec    0    133 KBytes       
[ 19]   2.00-3.01   sec  21.4 MBytes   177 Mbits/sec    0    136 KBytes       
[ 21]   2.00-3.01   sec  21.4 MBytes   177 Mbits/sec    0    116 KBytes       
[ 23]   2.00-3.01   sec  20.5 MBytes   170 Mbits/sec    0    139 KBytes       
[SUM]   2.00-3.01   sec   210 MBytes  1.74 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   3.01-4.00   sec  35.6 MBytes   302 Mbits/sec    0    260 KBytes       
[  7]   3.01-4.00   sec  17.5 MBytes   148 Mbits/sec    0    133 KBytes       
[  9]   3.01-4.00   sec  18.3 MBytes   155 Mbits/sec    0    144 KBytes       
[ 11]   3.01-4.00   sec  34.6 MBytes   293 Mbits/sec    0    272 KBytes       
[ 13]   3.01-4.00   sec  17.5 MBytes   149 Mbits/sec    0    147 KBytes       
[ 15]   3.01-4.00   sec  18.2 MBytes   154 Mbits/sec    0    147 KBytes       
[ 17]   3.01-4.00   sec  18.6 MBytes   157 Mbits/sec    0    146 KBytes       
[ 19]   3.01-4.00   sec  17.7 MBytes   150 Mbits/sec    0    146 KBytes       
[ 21]   3.01-4.00   sec  17.5 MBytes   149 Mbits/sec    0    144 KBytes       
[ 23]   3.01-4.00   sec  18.5 MBytes   157 Mbits/sec    0    148 KBytes       
[SUM]   3.01-4.00   sec   214 MBytes  1.82 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   4.00-5.00   sec  35.3 MBytes   296 Mbits/sec    0    260 KBytes       
[  7]   4.00-5.00   sec  17.8 MBytes   150 Mbits/sec    0    133 KBytes       
[  9]   4.00-5.00   sec  17.8 MBytes   149 Mbits/sec    0    144 KBytes       
[ 11]   4.00-5.00   sec  34.9 MBytes   293 Mbits/sec    0    272 KBytes       
[ 13]   4.00-5.00   sec  18.0 MBytes   151 Mbits/sec    0    147 KBytes       
[ 15]   4.00-5.00   sec  17.7 MBytes   149 Mbits/sec    0    147 KBytes       
[ 17]   4.00-5.00   sec  17.6 MBytes   148 Mbits/sec    0    146 KBytes       
[ 19]   4.00-5.00   sec  17.7 MBytes   149 Mbits/sec    0    146 KBytes       
[ 21]   4.00-5.00   sec  18.0 MBytes   151 Mbits/sec    0    144 KBytes       
[ 23]   4.00-5.00   sec  17.6 MBytes   148 Mbits/sec    0    148 KBytes       
[SUM]   4.00-5.00   sec   212 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   5.00-6.00   sec  34.8 MBytes   292 Mbits/sec    0    260 KBytes       
[  7]   5.00-6.00   sec  17.6 MBytes   148 Mbits/sec    0    133 KBytes       
[  9]   5.00-6.00   sec  17.5 MBytes   147 Mbits/sec    0    144 KBytes       
[ 11]   5.00-6.00   sec  35.4 MBytes   297 Mbits/sec    0    272 KBytes       
[ 13]   5.00-6.00   sec  17.5 MBytes   147 Mbits/sec    0    147 KBytes       
[ 15]   5.00-6.00   sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 17]   5.00-6.00   sec  17.5 MBytes   147 Mbits/sec    0    146 KBytes       
[ 19]   5.00-6.00   sec  17.5 MBytes   147 Mbits/sec    0    146 KBytes       
[ 21]   5.00-6.00   sec  17.5 MBytes   147 Mbits/sec    0    144 KBytes       
[ 23]   5.00-6.00   sec  17.5 MBytes   147 Mbits/sec    0    148 KBytes       
[SUM]   5.00-6.00   sec   211 MBytes  1.77 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   6.00-7.00   sec  35.0 MBytes   294 Mbits/sec    0    260 KBytes       
[  7]   6.00-7.00   sec  17.8 MBytes   150 Mbits/sec    0    133 KBytes       
[  9]   6.00-7.00   sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[ 11]   6.00-7.00   sec  35.0 MBytes   294 Mbits/sec    0    272 KBytes       
[ 13]   6.00-7.00   sec  17.6 MBytes   148 Mbits/sec    0    147 KBytes       
[ 15]   6.00-7.00   sec  17.6 MBytes   148 Mbits/sec    0    147 KBytes       
[ 17]   6.00-7.00   sec  17.6 MBytes   148 Mbits/sec    0    146 KBytes       
[ 19]   6.00-7.00   sec  18.0 MBytes   151 Mbits/sec    0    146 KBytes       
[ 21]   6.00-7.00   sec  17.6 MBytes   148 Mbits/sec    0    144 KBytes       
[ 23]   6.00-7.00   sec  17.6 MBytes   148 Mbits/sec    0    148 KBytes       
[SUM]   6.00-7.00   sec   212 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   7.00-8.00   sec  35.4 MBytes   297 Mbits/sec    0    260 KBytes       
[  7]   7.00-8.00   sec  17.6 MBytes   148 Mbits/sec    0    133 KBytes       
[  9]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    144 KBytes       
[ 11]   7.00-8.00   sec  35.1 MBytes   295 Mbits/sec    0    272 KBytes       
[ 13]   7.00-8.00   sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 15]   7.00-8.00   sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 17]   7.00-8.00   sec  17.9 MBytes   150 Mbits/sec    0    146 KBytes       
[ 19]   7.00-8.00   sec  17.5 MBytes   147 Mbits/sec    0    146 KBytes       
[ 21]   7.00-8.00   sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[ 23]   7.00-8.00   sec  17.9 MBytes   150 Mbits/sec    0    148 KBytes       
[SUM]   7.00-8.00   sec   213 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   8.00-9.00   sec  34.9 MBytes   293 Mbits/sec    0    260 KBytes       
[  7]   8.00-9.00   sec  17.8 MBytes   149 Mbits/sec    0    133 KBytes       
[  9]   8.00-9.00   sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[ 11]   8.00-9.00   sec  35.6 MBytes   299 Mbits/sec    0    272 KBytes       
[ 13]   8.00-9.00   sec  17.5 MBytes   147 Mbits/sec    0    147 KBytes       
[ 15]   8.00-9.00   sec  17.5 MBytes   147 Mbits/sec    0    147 KBytes       
[ 17]   8.00-9.00   sec  17.5 MBytes   147 Mbits/sec    0    146 KBytes       
[ 19]   8.00-9.00   sec  17.9 MBytes   150 Mbits/sec    0    146 KBytes       
[ 21]   8.00-9.00   sec  17.5 MBytes   147 Mbits/sec    0    144 KBytes       
[ 23]   8.00-9.00   sec  17.5 MBytes   147 Mbits/sec    0    148 KBytes       
[SUM]   8.00-9.00   sec   212 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   9.00-10.00  sec  35.5 MBytes   298 Mbits/sec    0    260 KBytes       
[  7]   9.00-10.00  sec  17.5 MBytes   147 Mbits/sec    0    133 KBytes       
[  9]   9.00-10.00  sec  17.5 MBytes   147 Mbits/sec    0    144 KBytes       
[ 11]   9.00-10.00  sec  34.9 MBytes   293 Mbits/sec    0    272 KBytes       
[ 13]   9.00-10.00  sec  17.9 MBytes   150 Mbits/sec    0    147 KBytes       
[ 15]   9.00-10.00  sec  17.5 MBytes   147 Mbits/sec    0    147 KBytes       
[ 17]   9.00-10.00  sec  17.9 MBytes   150 Mbits/sec    0    146 KBytes       
[ 19]   9.00-10.00  sec  17.5 MBytes   147 Mbits/sec    0    146 KBytes       
[ 21]   9.00-10.00  sec  17.9 MBytes   150 Mbits/sec    0    144 KBytes       
[ 23]   9.00-10.00  sec  17.9 MBytes   150 Mbits/sec    0    148 KBytes       
[SUM]   9.00-10.00  sec   212 MBytes  1.78 Gbits/sec    0             
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate         Retr
[  5]   0.00-10.00  sec   311 MBytes   261 Mbits/sec    0             sender
[  5]   0.00-10.00  sec   310 MBytes   260 Mbits/sec                  receiver
[  7]   0.00-10.00  sec   188 MBytes   157 Mbits/sec    0             sender
[  7]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[  9]   0.00-10.00  sec   188 MBytes   157 Mbits/sec    0             sender
[  9]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[ 11]   0.00-10.00  sec   310 MBytes   260 Mbits/sec    0             sender
[ 11]   0.00-10.00  sec   308 MBytes   259 Mbits/sec                  receiver
[ 13]   0.00-10.00  sec   188 MBytes   158 Mbits/sec    0             sender
[ 13]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[ 15]   0.00-10.00  sec   187 MBytes   157 Mbits/sec    0             sender
[ 15]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[ 17]   0.00-10.00  sec   187 MBytes   157 Mbits/sec    0             sender
[ 17]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[ 19]   0.00-10.00  sec   188 MBytes   158 Mbits/sec    0             sender
[ 19]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[ 21]   0.00-10.00  sec   188 MBytes   157 Mbits/sec    0             sender
[ 21]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[ 23]   0.00-10.00  sec   188 MBytes   157 Mbits/sec    0             sender
[ 23]   0.00-10.00  sec   187 MBytes   157 Mbits/sec                  receiver
[SUM]   0.00-10.00  sec  2.07 GBytes  1.78 Gbits/sec    0             sender
[SUM]   0.00-10.00  sec  2.06 GBytes  1.77 Gbits/sec                  receiver

Download test. This is a single run. I actually did it three times, and got results in the range of 2.1-2.3 Gbps.

I’m actually seeing more strain on the CPU when downloading from the server. One core is pegged, and another is about about 50-60 percent usage.

~]$ iperf3 -c 10.0.4.135 -P 10 -R
Connecting to host 10.0.4.135, port 5201
Reverse mode, remote host 10.0.4.135 is sending
[  5] local 10.0.4.139 port 36642 connected to 10.0.4.135 port 5201
[  7] local 10.0.4.139 port 36644 connected to 10.0.4.135 port 5201
[  9] local 10.0.4.139 port 36646 connected to 10.0.4.135 port 5201
[ 11] local 10.0.4.139 port 36648 connected to 10.0.4.135 port 5201
[ 13] local 10.0.4.139 port 36650 connected to 10.0.4.135 port 5201
[ 15] local 10.0.4.139 port 36652 connected to 10.0.4.135 port 5201
[ 17] local 10.0.4.139 port 36654 connected to 10.0.4.135 port 5201
[ 19] local 10.0.4.139 port 36656 connected to 10.0.4.135 port 5201
[ 21] local 10.0.4.139 port 36658 connected to 10.0.4.135 port 5201
[ 23] local 10.0.4.139 port 36660 connected to 10.0.4.135 port 5201
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  34.8 MBytes   292 Mbits/sec                  
[  7]   0.00-1.00   sec  29.9 MBytes   251 Mbits/sec                  
[  9]   0.00-1.00   sec  26.6 MBytes   223 Mbits/sec                  
[ 11]   0.00-1.00   sec  29.1 MBytes   244 Mbits/sec                  
[ 13]   0.00-1.00   sec  29.9 MBytes   250 Mbits/sec                  
[ 15]   0.00-1.00   sec  20.0 MBytes   168 Mbits/sec                  
[ 17]   0.00-1.00   sec  27.1 MBytes   227 Mbits/sec                  
[ 19]   0.00-1.00   sec  26.0 MBytes   218 Mbits/sec                  
[ 21]   0.00-1.00   sec  28.1 MBytes   236 Mbits/sec                  
[ 23]   0.00-1.00   sec  26.3 MBytes   221 Mbits/sec                  
[SUM]   0.00-1.00   sec   278 MBytes  2.33 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   1.00-2.00   sec  31.1 MBytes   261 Mbits/sec                  
[  7]   1.00-2.00   sec  28.5 MBytes   239 Mbits/sec                  
[  9]   1.00-2.00   sec  31.7 MBytes   266 Mbits/sec                  
[ 11]   1.00-2.00   sec  27.8 MBytes   234 Mbits/sec                  
[ 13]   1.00-2.00   sec  27.8 MBytes   233 Mbits/sec                  
[ 15]   1.00-2.00   sec  29.8 MBytes   250 Mbits/sec                  
[ 17]   1.00-2.00   sec  18.5 MBytes   155 Mbits/sec                  
[ 19]   1.00-2.00   sec  27.8 MBytes   234 Mbits/sec                  
[ 21]   1.00-2.00   sec  27.6 MBytes   231 Mbits/sec                  
[ 23]   1.00-2.00   sec  28.0 MBytes   235 Mbits/sec                  
[SUM]   1.00-2.00   sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   2.00-3.00   sec  31.7 MBytes   266 Mbits/sec                  
[  7]   2.00-3.00   sec  31.4 MBytes   264 Mbits/sec                  
[  9]   2.00-3.00   sec  18.9 MBytes   158 Mbits/sec                  
[ 11]   2.00-3.00   sec  29.5 MBytes   248 Mbits/sec                  
[ 13]   2.00-3.00   sec  32.0 MBytes   269 Mbits/sec                  
[ 15]   2.00-3.00   sec  28.1 MBytes   235 Mbits/sec                  
[ 17]   2.00-3.00   sec  26.9 MBytes   226 Mbits/sec                  
[ 19]   2.00-3.00   sec  25.9 MBytes   217 Mbits/sec                  
[ 21]   2.00-3.00   sec  28.1 MBytes   236 Mbits/sec                  
[ 23]   2.00-3.00   sec  26.2 MBytes   220 Mbits/sec                  
[SUM]   2.00-3.00   sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   3.00-4.00   sec  31.8 MBytes   266 Mbits/sec                  
[  7]   3.00-4.00   sec  27.8 MBytes   233 Mbits/sec                  
[  9]   3.00-4.00   sec  26.4 MBytes   222 Mbits/sec                  
[ 11]   3.00-4.00   sec  28.8 MBytes   241 Mbits/sec                  
[ 13]   3.00-4.00   sec  30.0 MBytes   252 Mbits/sec                  
[ 15]   3.00-4.00   sec  28.4 MBytes   238 Mbits/sec                  
[ 17]   3.00-4.00   sec  26.7 MBytes   224 Mbits/sec                  
[ 19]   3.00-4.00   sec  27.9 MBytes   234 Mbits/sec                  
[ 21]   3.00-4.00   sec  26.2 MBytes   220 Mbits/sec                  
[ 23]   3.00-4.00   sec  25.2 MBytes   211 Mbits/sec                  
[SUM]   3.00-4.00   sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   4.00-5.00   sec  29.8 MBytes   250 Mbits/sec                  
[  7]   4.00-5.00   sec  30.7 MBytes   258 Mbits/sec                  
[  9]   4.00-5.00   sec  30.3 MBytes   254 Mbits/sec                  
[ 11]   4.00-5.00   sec  28.4 MBytes   239 Mbits/sec                  
[ 13]   4.00-5.00   sec  28.1 MBytes   235 Mbits/sec                  
[ 15]   4.00-5.00   sec  28.8 MBytes   242 Mbits/sec                  
[ 17]   4.00-5.00   sec  28.4 MBytes   238 Mbits/sec                  
[ 19]   4.00-5.00   sec  27.0 MBytes   226 Mbits/sec                  
[ 21]   4.00-5.00   sec  22.2 MBytes   187 Mbits/sec                  
[ 23]   4.00-5.00   sec  26.0 MBytes   218 Mbits/sec                  
[SUM]   4.00-5.00   sec   280 MBytes  2.35 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   5.00-6.00   sec  32.1 MBytes   270 Mbits/sec                  
[  7]   5.00-6.00   sec  29.8 MBytes   250 Mbits/sec                  
[  9]   5.00-6.00   sec  29.6 MBytes   249 Mbits/sec                  
[ 11]   5.00-6.00   sec  28.4 MBytes   238 Mbits/sec                  
[ 13]   5.00-6.00   sec  19.7 MBytes   165 Mbits/sec                  
[ 15]   5.00-6.00   sec  29.1 MBytes   244 Mbits/sec                  
[ 17]   5.00-6.00   sec  27.5 MBytes   230 Mbits/sec                  
[ 19]   5.00-6.00   sec  27.9 MBytes   234 Mbits/sec                  
[ 21]   5.00-6.00   sec  26.3 MBytes   221 Mbits/sec                  
[ 23]   5.00-6.00   sec  28.6 MBytes   240 Mbits/sec                  
[SUM]   5.00-6.00   sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   6.00-7.00   sec  32.4 MBytes   272 Mbits/sec                  
[  7]   6.00-7.00   sec  28.7 MBytes   241 Mbits/sec                  
[  9]   6.00-7.00   sec  28.5 MBytes   239 Mbits/sec                  
[ 11]   6.00-7.00   sec  28.0 MBytes   235 Mbits/sec                  
[ 13]   6.00-7.00   sec  26.7 MBytes   224 Mbits/sec                  
[ 15]   6.00-7.00   sec  27.3 MBytes   229 Mbits/sec                  
[ 17]   6.00-7.00   sec  28.4 MBytes   238 Mbits/sec                  
[ 19]   6.00-7.00   sec  27.2 MBytes   228 Mbits/sec                  
[ 21]   6.00-7.00   sec  25.7 MBytes   215 Mbits/sec                  
[ 23]   6.00-7.00   sec  26.3 MBytes   221 Mbits/sec                  
[SUM]   6.00-7.00   sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   7.00-8.00   sec  30.0 MBytes   252 Mbits/sec                  
[  7]   7.00-8.00   sec  29.4 MBytes   246 Mbits/sec                  
[  9]   7.00-8.00   sec  28.3 MBytes   238 Mbits/sec                  
[ 11]   7.00-8.00   sec  26.9 MBytes   226 Mbits/sec                  
[ 13]   7.00-8.00   sec  28.6 MBytes   240 Mbits/sec                  
[ 15]   7.00-8.00   sec  28.1 MBytes   236 Mbits/sec                  
[ 17]   7.00-8.00   sec  27.2 MBytes   228 Mbits/sec                  
[ 19]   7.00-8.00   sec  27.6 MBytes   231 Mbits/sec                  
[ 21]   7.00-8.00   sec  27.2 MBytes   229 Mbits/sec                  
[ 23]   7.00-8.00   sec  25.9 MBytes   218 Mbits/sec                  
[SUM]   7.00-8.00   sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   8.00-9.00   sec  36.7 MBytes   308 Mbits/sec                  
[  7]   8.00-9.00   sec  14.2 MBytes   119 Mbits/sec                  
[  9]   8.00-9.00   sec  34.0 MBytes   285 Mbits/sec                  
[ 11]   8.00-9.00   sec  35.8 MBytes   300 Mbits/sec                  
[ 13]   8.00-9.00   sec  32.2 MBytes   270 Mbits/sec                  
[ 15]   8.00-9.00   sec  23.3 MBytes   195 Mbits/sec                  
[ 17]   8.00-9.00   sec  34.0 MBytes   285 Mbits/sec                  
[ 19]   8.00-9.00   sec  13.0 MBytes   109 Mbits/sec                  
[ 21]   8.00-9.00   sec  26.1 MBytes   219 Mbits/sec                  
[ 23]   8.00-9.00   sec  29.2 MBytes   245 Mbits/sec                  
[SUM]   8.00-9.00   sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[  5]   9.00-10.00  sec  32.1 MBytes   269 Mbits/sec                  
[  7]   9.00-10.00  sec  29.7 MBytes   249 Mbits/sec                  
[  9]   9.00-10.00  sec  21.6 MBytes   181 Mbits/sec                  
[ 11]   9.00-10.00  sec  33.2 MBytes   278 Mbits/sec                  
[ 13]   9.00-10.00  sec  21.4 MBytes   179 Mbits/sec                  
[ 15]   9.00-10.00  sec  30.7 MBytes   258 Mbits/sec                  
[ 17]   9.00-10.00  sec  30.1 MBytes   253 Mbits/sec                  
[ 19]   9.00-10.00  sec  27.1 MBytes   228 Mbits/sec                  
[ 21]   9.00-10.00  sec  23.8 MBytes   199 Mbits/sec                  
[ 23]   9.00-10.00  sec  29.5 MBytes   248 Mbits/sec                  
[SUM]   9.00-10.00  sec   279 MBytes  2.34 Gbits/sec                  
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-10.00  sec   323 MBytes   271 Mbits/sec                  sender
[  5]   0.00-10.00  sec   322 MBytes   271 Mbits/sec                  receiver
[  7]   0.00-10.00  sec   280 MBytes   235 Mbits/sec                  sender
[  7]   0.00-10.00  sec   280 MBytes   235 Mbits/sec                  receiver
[  9]   0.00-10.00  sec   276 MBytes   232 Mbits/sec                  sender
[  9]   0.00-10.00  sec   276 MBytes   231 Mbits/sec                  receiver
[ 11]   0.00-10.00  sec   296 MBytes   248 Mbits/sec                  sender
[ 11]   0.00-10.00  sec   296 MBytes   248 Mbits/sec                  receiver
[ 13]   0.00-10.00  sec   276 MBytes   232 Mbits/sec                  sender
[ 13]   0.00-10.00  sec   276 MBytes   232 Mbits/sec                  receiver
[ 15]   0.00-10.00  sec   274 MBytes   230 Mbits/sec                  sender
[ 15]   0.00-10.00  sec   274 MBytes   229 Mbits/sec                  receiver
[ 17]   0.00-10.00  sec   275 MBytes   231 Mbits/sec                  sender
[ 17]   0.00-10.00  sec   275 MBytes   230 Mbits/sec                  receiver
[ 19]   0.00-10.00  sec   257 MBytes   216 Mbits/sec                  sender
[ 19]   0.00-10.00  sec   257 MBytes   216 Mbits/sec                  receiver
[ 21]   0.00-10.00  sec   261 MBytes   219 Mbits/sec                  sender
[ 21]   0.00-10.00  sec   261 MBytes   219 Mbits/sec                  receiver
[ 23]   0.00-10.00  sec   272 MBytes   228 Mbits/sec                  sender
[ 23]   0.00-10.00  sec   271 MBytes   228 Mbits/sec                  receiver
[SUM]   0.00-10.00  sec  2.72 GBytes  2.34 Gbits/sec                  sender
[SUM]   0.00-10.00  sec  2.72 GBytes  2.34 Gbits/sec                  receiver

I’m working on getting it to work on reboot without unplugging and plugging it back in, now.
Unlike in the HOWTO I linked in the original post, the following command, while it does modeswitch the device from showing up as an 8151 to an 8156, does not survive restart.

~]$ sudo usb_modeswitch -v 0bda -p 8151 -V 0bda -P 8156 -M 555342430860d9a9c0000000800006e0000000000000000000000000000000

I’ve looked at sample udev rules, and they confuse the crap out of me, so I think the simpler thing to do would be to set up a run-on-boot service via systemd to run a script that executes the above command.

This looks simple enough: systemd/FAQ - ArchWiki (run a script during the boot process).

One thing I’m not yet sure about: what target should I set? The example uses multi-user.target, which as I understand it means the system is up and ready for users to login. That’d certainly be a fine time to run the script, but would there be a downside to that?

EDIT: Systemd Service Enabled; USB Modesetting starts the NIC correctly on boot.

~]$ cat /etc/systemd/system/realtek8156enabler.service 
[Unit]
Description=Sabrent 2.5G USB 3.0 (Realtek 8156 Chipset) Enabler - USB Mode Switcher
 
[Service]
ExecStart=/rootScripts/enableSabrentUSB2-5G.sh
 
[Install]
WantedBy=multi-user.target

And here’s the script (be sure to sudo chmod +x + scriptName:

#/rootScripts/enableSabrentUSB2-5G.sh
# (The name can be whatever you like. I just wanted to remind myself what hardware I have that uses this chipset.)
-----------
#!/bin/bash

# Run usb_modeswitch command to put the adapter in NIC mode.
# Source: https://forum.manjaro.org/t/sabrent-usb-2-5g-ethernet-adapter-realtek-8152-chipset-drivers-from-aur/55483

sh -c "usb_modeswitch -v 0bda -p 8151 -V 0bda -P 8156 -M 555342430860d9a9c0000000800006e0000000000000000000000000000000"