Issue: The ethernet port on the Syba SD-PEX50100 PCI-E card does not work properly in Debian Bullseye (kernel 5.10.0-11-amd64).
In Bullseye, with kernel 5.10.0-11-amd64, the ethernet card starts randomizing the MAC address which causes issues with ISPs that DHCP servers that lock-on to MAC addresses. I also think the ethernet port does not work in general in Bullseye but I am not sure how to prove that bigger claim.
The card works just fine in Debian Buster with kernel 4.19.0-11-amd64. It never fails to obtain a lease from the ISP DHCP server and its real MAC address is always used because it never gets randomized.
I have used a pair of Debian Live USB sticks to boot from (one containing Bullseye and another containing Buster) to prove that the card works on one and not the other. In these environments, the card is managed by NetworkManager.service. I have also tested it with a hard-drive installation of Bullseye where the card is managed via networking.service instead and the same issues occur as with the Bullseye Live image that uses NetworkManager.service.
In Bullseye, the /var/log/messages file shows kernel logs that indicate that there are issues during boot up with the PCI-E card. Those logs do not occur at all in Debian Buster. This is why I think the issue is in the kernel.
The kernel logs indicating issues in Bullseye include a warning of a "host failure" by xhci_hcd, and several write/read errors by the ax88179 ethernet driver/module for the card, as follows:
Feb 22 17:22:53 server1 kernel: [ 1.380198] xhci_hcd 0000:1c:00.0: xHCI Host Controller
Feb 22 17:22:53 server1 kernel: [ 1.380205] xhci_hcd 0000:1c:00.0: new USB bus registered, assigned bus number 5
Feb 22 17:22:53 server1 kernel: [ 1.380209] xhci_hcd 0000:1c:00.0: Host supports USB 3.0 SuperSpeed
Feb 22 17:22:53 server1 kernel: [ 1.380260] usb usb5: New USB device found, idVendor=1d6b, idProduct=0003, bcdDevice= 5.10
Feb 22 17:22:53 server1 kernel: [ 1.380261] usb usb5: New USB device strings: Mfr=3, Product=2, SerialNumber=1
Feb 22 17:22:53 server1 kernel: [ 1.380263] usb usb5: Product: xHCI Host Controller
Feb 22 17:22:53 server1 kernel: [ 1.380264] usb usb5: Manufacturer: Linux 5.10.0-11-amd64 xhci-hcd
Feb 22 17:22:53 server1 kernel: [ 1.380265] usb usb5: SerialNumber: 0000:1c:00.0
Feb 22 17:22:53 server1 kernel: [ 1.380396] hub 5-0:1.0: USB hub found
Feb 22 17:22:53 server1 kernel: [ 1.380411] hub 5-0:1.0: 4 ports detected
Feb 22 17:22:53 server1 kernel: [ 5.508457] ax88179_178a 5-1:1.0 eth0: register 'ax88179_178a' at usb-0000:1c:00.0-1, ASIX AX88179 USB 3.0 Gigabit Ethernet, 00:11:22:33:44:55
Feb 22 17:23:25 server1 kernel: [ 39.576966] xhci_hcd 0000:1c:00.0: WARNING: Host System Error
Feb 22 17:26:00 server1 kernel: [ 194.596335] ax88179_178a 5-1:1.0 enx001122334455: Failed to read reg index 0x0002: -22
Feb 22 17:26:00 server1 kernel: [ 194.596338] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0002: -22
Feb 22 17:26:11 server1 kernel: [ 205.378965] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0002: -22
Feb 22 17:26:11 server1 kernel: [ 205.378969] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0002: -22
Feb 22 17:26:11 server1 kernel: [ 205.585506] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693515] ax88179_178a 5-1:1.0 enx001122334455: Failed to read reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693524] ax88179_178a 5-1:1.0 enx001122334455: Failed to read reg index 0x0006: -22
Feb 22 17:26:11 server1 kernel: [ 205.693527] ax88179_178a 5-1:1.0 enx001122334455: invalid MAC address, using random
Feb 22 17:26:11 server1 kernel: [ 205.693532] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0006: -22
Feb 22 17:26:11 server1 kernel: [ 205.693535] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0005: -22
Feb 22 17:26:11 server1 kernel: [ 205.693538] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693541] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693544] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693547] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693550] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0002: -22
Feb 22 17:26:11 server1 kernel: [ 205.693553] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693555] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0002: -22
Feb 22 17:26:11 server1 kernel: [ 205.693561] ax88179_178a 5-1:1.0 enx001122334455: Failed to read reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693564] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0001: -22
Feb 22 17:26:11 server1 kernel: [ 205.693567] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x001f: -22
Feb 22 17:26:11 server1 kernel: [ 205.693570] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x0019: -22
Feb 22 17:26:11 server1 kernel: [ 205.693573] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x001f: -22
Feb 22 17:26:11 server1 kernel: [ 205.693576] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x000d: -22
Feb 22 17:26:11 server1 kernel: [ 205.693579] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x000e: -22
Feb 22 17:26:11 server1 kernel: [ 205.693581] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x000d: -22
Feb 22 17:26:11 server1 kernel: [ 205.693586] ax88179_178a 5-1:1.0 enx001122334455: Failed to read reg index 0x000e: -22
Feb 22 17:26:11 server1 kernel: [ 205.693590] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x000d: -22
Feb 22 17:26:11 server1 kernel: [ 205.693593] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x000e: -22
Feb 22 17:26:11 server1 kernel: [ 205.693595] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x000d: -22
Feb 22 17:26:11 server1 kernel: [ 205.693598] ax88179_178a 5-1:1.0 enx001122334455: Failed to write reg index 0x000e: -22
Feb 22 17:26:11 server1 kernel: [ 205.693604] ax88179_178a 5-1:1.0 enx001122334455: Failed to read reg index 0x0000: -22
This is my first time reporting an issue to this email list (or Debian), so I am not sure what other information to provide or if I need to open a bug report somewhere. So, if this is not the correct way to report the issue and/or not sufficient information to investigate it, I would appreciate your guidance.