Ubuntu 20.4.1 no wired ethernet

I have installed Ubuntu 20.4 on a new build with the MSI Z490 motherboard but the wired ethernet is not working. The ubuntu distro minimal so installing the driver from Realtec fails because the tools are not available. I would be grateful for any useful advice. Here are some diagnostics which might help.

>>>>>>>>>>>>>>>:~$ lspci -nnk | grep -ia3 net
Subsystem: Micro-Star International Co., Ltd. [MSI] GK208 HDMI/DP Audio Controller [1462:8c93]
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel
03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8125 2.5GbE Controller [10ec:8125] (rev 04)
Subsystem: Micro-Star International Co., Ltd. [MSI] RTL8125 2.5GbE Controller [1462:7c75]
Kernel modules: r8169

>>>>>>>>>>>>>>>:~$ cat /etc/network/interfaces
/etc/network/interfaces: No such file or directory

>>>>>>>>>>>>>>>:~$ ls /lib/modules/5.4.0-42-generic/kernel/drivers/net/ethernet/realtek/
8139cp.ko 8139too.ko atp.ko r8169.ko

>>>>>>>>>>>>>>>:~$ ls /lib/modules/5.4.0-42-generic/kernel/drivers/net/ethernet/realtek/r8169.ko
/lib/modules/5.4.0-42-generic/kernel/drivers/net/ethernet/realtek/r8169.ko
>>>>>>>>>>>>>>>:~$

>>>>>>>>>>>>>>>:~$ cat /etc/modules-load.d/modules.conf
# /etc/modules: kernel modules to load at boot time.
#
# This file contains the names of kernel modules that should be loaded
# at boot time, one per line. Lines beginning with "#" are ignored.

>>>>>>>>>>>>>>>:~$ lsmod | grep 8169
r8169 90112 0

>>>>>>>>>>>>>>:~$ sudo lshw -C network
*-network UNCLAIMED
description: Ethernet controller
product: RTL8125 2.5GbE Controller
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:03:00.0
version: 04
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress msix vpd cap_list
configuration: latency=0
resources: ioport:3000(size=256) memory:ab200000-ab20ffff memory:ab210000-ab213fff

>>>>>> System settings shows only NVIDIA drivers.