• I found a workaround, which is to add a static ARP entry for the Linux server. So I'm happy for you to close this thread if you like. Pinging the desktop from the ubuntu server (called quartz) resolves the connectivity issue (as does clearing the ARP cache on the windows machine). I suspect this is an ARP on Windows 11…
  • Prior logs (before device rename) [ 4.880214] r8169 0000:07:00.0 eth0: RTL8125B, 00:e0:4c:65:xx:xx, XID 641, IRQ 27 [ 4.916083] r8169 0000:07:00.0 eth0: jumbo features [frames: 9194 bytes, tx checksumming: ko]
  • Logs from Unbuntu server [ 5.121151] r8169 0000:07:00.0 ens1: renamed from eth0 [ 11.514456] r8169 0000:07:00.0 ens1: Link is Down [ 14.556062] r8169 0000:07:00.0 ens1: Link is Up - 2.5Gbps/Full - flow control rx/tx [ 14.556085] IPv6: ADDRCONF(NETDEV_CHANGE): ens1: link becomes ready