Unclear how to network bridge

[eiger3970]

Issue:
I cannot ping between the 2 machines, since adding a Proxmox Linux Bridge via GUI.

Attempt to resolve:
I followed the Proxmox Network Configuration guide > Routed Configuration.

Setup:
My network topology:
Internet > mobile > SIM > Wi-Fi hotspot on > Wi-Fi NIC > machine0 > machine0's Ethernet NIC > Ethernet cable > Hub > Ethernet cable > machine1's Ethernet NIC > machine1.

Machine0:

linuxmint@linuxmint:~$ 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: enp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 88:d7:f6:c9:08:eb brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.120/24 brd 192.168.1.255 scope global noprefixroute enp3s0
       valid_lft forever preferred_lft forever
    inet6 fe80::5174:24eb:7975:5f6f/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
3: wlx503eaae4a007: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 50:3e:aa:e4:a0:07 brd ff:ff:ff:ff:ff:ff
    inet 172.20.10.2/28 brd 172.20.10.15 scope global dynamic noprefixroute wlx503eaae4a007
       valid_lft 82117sec preferred_lft 82117sec
    inet6 fe80::a3ed:3607:c974:ea70/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
linuxmint@linuxmint:~$ cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
# Include files from /etc/network/interfaces.d:

auto lo
iface lo inet loopback

auto enps30
face enps30 inet static
address 192.168.1.120/24

Internet is bridged from machine0 to machine1.
Machine0:

iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -j MASQUERADE
cat /etc/sysctl.conf
net.ipv4.ip_forward = 1

Machine1:

root@proxmox:~# ip a
: 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
: enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
    link/ether 40:16:7e:37:21:af brd ff:ff:ff:ff:ff:ff
    inet6 fe80::4216:7eff:fe37:21af/64 scope link
        valid_lft forever preferred_lft forever
: enp2s0 <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
    link/ether 40:16:7e:37:21:b0 brd ff:ff:ff:ff:ff:ff
: wlp7s0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
    link/ether ac:12:03:d7:ac:c1 brd ff:ff:ff:ff:ff:ff
: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000
    link/ether ea:f3:30:1b:59:ec brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.140/24 brd 192.168.1.255 scope global vmbr0
        valid_lft forever preferred_lft forever
    inet6 fe80::e8f3:30ff:fe1b:59ec/64 scople link
        valid_lft forever preferred_lft forever
root@proxmox:~# cat /etc/network/interfaces
network interface settings: autogenerated
Please do NOT modify this file directly, unless you know what
you're doing.

If you want to manage parts of the network configuration manually,
please utlise the 'source' or 'source-directory' directives to do
so.
PVE will preserve these directives, but will NOT read its network
configuration from sourced files, so do not attempt to move any of
the PVE managed interfaces into external files!

auto lo
iface lo inet loopback

auto enp1s0
iface enp1s0 inet manual
    address 192.168.1.140/24
    gateway 192.168.1.120

auto enp2s0
iface enp2s0 inet manual

auto vmbr0
iface vmbr0 inet static
    address 192.168.1.140/24
    gateway 192.168.1.120
    bridge-ports none
    bridge-stp off
    bridge-fd 0

 

[eiger3970]

Restored original interfaces file and still cannot ping machine0 to machine1.
Attempting to reinstall Proxmox 6.3, however all 8 USB ports don't see the USB at BIOS to select as 1st Boot priority.
Keyboard in machine1 Proxmox machine works in all 8 USB ports.
USB works in machine0.

 

[eiger3970]

Fixed machine's BIOS which was not allowing selection to boot USB 1st.
Now uninstalling ZFS/RAID10 all 4 disks, otherwise upon reinstall of Proxmox, the same faulty bridge settings appear.
Question: shred or dd?
Shred is said to be faster. However if I can write a dd command that dd's the first 128MB of all 4 disks, this sounds quicker. Anyone able to assist with the dd command to dd the 1st 128MB?

 

[eiger3970]

Is there a quicker way to reinstall Proxmox without having the previous (problematic) version restored by ZFS?
Deleting the first 128MB might be enough, however I haven't figured out a command to do that yet?
I manually dd all 4 disks

dd if=/dev/zero of=/dev/sd<x> bs=100M status=progress

as the following code produces errors like

root@proxmox:~# zpool labelclear /dev/sde
failed to clear label for /dev/sde
root@proxmox:~# zpool labelclear /dev/sdd
failed to clear label for /dev/sdd
root@proxmox:~# zpool labelclear /dev/sdc
failed to clear label for /dev/sdc
root@proxmox:~# zpool labelclear /dev/sdb
/dev/sdb is a member (ACTIVE) of pool "rpool"
root@proxmox:~# zpool labelclear /dev/sda
/dev/sda is a member (ACTIVE) of pool "rpool"