Have I setup networking correctly?

[nickshanks]

I run Proxmox off a Hetzner dedi. Getting it installed was a pain but did it in the end. Have I configured networking properly?

/etc/network/interfaces:

auto lo

iface lo inet loopback
iface eno1 inet manual

auto vmbr0

iface vmbr0 inet static
      address      123.123.123.123/26
      gateway      123.123.123.124
      bridge-ports eno1
      bridge-stp   off
      bridge-fd    0

source /etc/network/interfaces.d/*

/etc/network/interfaces.d/sdn:

#version:6
auto vnet0

iface vnet0
        address 10.0.0.1/24
        post-up iptables -t nat -A POSTROUTING -s '10.0.0.0/24' -o vmbr0 -j SNAT --to-source 123.123.123.123
        post-down iptables -t nat -D POSTROUTING -s '10.0.0.0/24' -o vmbr0 -j SNAT --to-source 123.123.123.123
        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
        post-up iptables -t nat -A PREROUTING -p tcp -d 123.123.123.123 --dport 80 -i vmbr0 -j DNAT --to-destination 10.0.0.100:80
        post-up iptables -t nat -A PREROUTING -p tcp -d 123.123.123.123 --dport 443 -i vmbr0 -j DNAT --to-destination 10.0.0.100:443
        post-up iptables -t nat -A PREROUTING -p tcp -d 123.123.123.123--dport 587 -i vmbr0 -j DNAT --to-destination 10.0.0.100:587
        post-up iptables -t nat -A PREROUTING -p tcp -d 123.123.123.123--dport 993 -i vmbr0 -j DNAT --to-destination 10.0.0.100:993
        post-up iptables -t nat -A PREROUTING -p tcp -d 123.123.123.123--dport 143 -i vmbr0 -j DNAT --to-destination 10.0.0.100:143
        post-up iptables -t nat -A PREROUTING -p tcp -d 123.123.123.123--dport 25 -i vmbr0 -j DNAT --to-destination 10.0.0.100:25
        post-up iptables -t nat -A PREROUTING -p tcp -d 123.123.123.123--dport 465 -i vmbr0 -j DNAT --to-destination 10.0.0.100:465
        post-up iptables -t nat -A PREROUTING -p udp -d 123.123.123.123--dport 33275 -i vmbr0 -j DNAT --to-destination 10.0.0.100:33275
        post-up iptables -t nat -A PREROUTING -p udp -d 123.123.123.123--dport 51820 -i vmbr0 -j DNAT --to-destination 10.0.0.100:51820
        bridge_ports none
        bridge_stp off
        bridge_fd 0
        ip-forward on