/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 utilize 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 <eth-interface>
iface <eth-interface> inet manual

auto vmbr0
iface vmbr0 inet manual
        bridge-ports <eth-interface>
        bridge-stp off
        bridge-fd 0
        bridge-vlan-aware yes
        bridge-vids 2-4094
        post-up   ethtool -K <eth-interface> gso off gro off tso off tx off rx off
        post-up   echo 1 > /proc/sys/net/ipv4/ip_forward
        post-up   iptables -t nat -A POSTROUTING -s '192.168.1.1/24' -o <eth-interface> -j MASQUERADE
        post-down iptables -t nat -D POSTROUTING -s '192.168.1.1/24' -o <eth-interface> -j MASQUERADE
        post-up   iptables -t raw -I PREROUTING -i fwbr+ -j CT --zone 1
        post-down iptables -t raw -D PREROUTING -i fwbr+ -j CT --zone 1

auto vmbr0.2
iface vmbr0.2 inet manual
#VLAN 2 Servers

auto vmbr0.3
iface vmbr0.3 inet manual
#VLAN 3 IoT

auto vmbr0.100
iface vmbr0.100 inet static
        address <pve-host-ip>/24
        gateway <management-network-gateway>
# VLAN 100 Management

source /etc/network/interfaces.d/*