No Network Access After Motherboard BIOS Update

On my Ubuntu 20.04 system, networking (ethernet) was working fine until I updated my ASRock B550M Pro4 motherboard's BIOS to the latest version. Now, whenever I boot into Ubuntu, there is no longer any access to the network.

$ ping 8.8.8.8
ping: connect: Network is unreachable

It also appears that my ethernet interface is disabled.

$ sudo lshw -C network

 *-network DISABLED
     description: Ethernet interface
     product: RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller

No ifconfig

Unable to install ifconfig because there is no internet access

No NetworkManager.state

Tried a few commands below, but they dont work:

$ cat /var/lib/NetworkManager/NetworkManager.state
cat: /var/lib/NetworkManager/NetworkManager.state: No such file or directory

$ cat /var/lib/NetworkManager
cat: /var/lib/NetworkManager: No such file or directory

and no output from running:

$ cat /etc/network/interfaces

Restarting networking service doesnt help

$ sudo systemctl restart systemd-networkd

3 network interfaces found

ip a shows 3 interfaces

• lo
• enp4so
• docker0

Output of ip r

$ ip r
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown

Output of ip a

$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
      valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
      valid_lft forever preferred_lft forever
2: enp4so: <BROADCAST,MULTICAST> mtu 15500 qdisc noop state DOWN group default qlen 1000
    link/ether a8:a1:59:64:4b:5b brd ff:ff:ff:ff:ff:ff
3: docker0: <NOCARRIER,BROADAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default

Ethernet is enabled in BIOS

In the BIOS settings, Onboard LAN is Enabled.

Internet access in Live Session

Able to ping google.com and ping 8.8.8.8

dkms and netplan

dksm not installed, and cannot be installed without network access.

$ cat /etc/netplan/*.yaml
# This is the network config written by 'subiquity'
network:
  ethernets:
    enp7so:
      dhcp4: true
    version: 2

Any suggestions on how to recover network access? Thanks!

Edit your /etc/netplan/*.yaml...

Change this...

# This is the network config written by 'subiquity'
network:
  ethernets:
    enp7so:
      dhcp4: true
    version: 2

To this...

# This is the network config written by 'subiquity'
network:
  version: 2
  renderer: networkd
  ethernets:
    enp4so:
      dhcp4: true
      optional: true

sudo netplan generate

sudo netplan apply

reboot