Wiregaurd proxmox setup (ip-transit)

📦 Step 1: Install WireGuard

apt update apt install wireguard wireguard-tools -y

📁 Step 2: Create WireGuard config

Create the tunnel config:

nano /etc/wireguard/wg0.conf

Paste your WireGuard config.

Inside the [Interface] section add:

PostUp = /etc/wireguard/up.sh PostDown = /etc/wireguard/down.sh

Example:

[Interface] PrivateKey = YOUR_PRIVATE_KEY Address = YOUR_WG_IP PostUp = /etc/wireguard/up.sh PostDown = /etc/wireguard/down.sh

[Peer] PublicKey = SERVER_KEY Endpoint = SERVER_IP:PORT AllowedIPs = 0.0.0.0/0 PersistentKeepalive = 25

Save the file.

📜 Step 3: Create persistent routing script

Create:

nano /etc/wireguard/up.sh

Paste:

#!/bin/bash

for ip in {113..117}; do ip rule add from 5.231.32.$ip/32 table 11 prio 1 ip route add 5.231.32.$ip/32 dev vmbr0 table 11 ip route add 5.231.32.$ip/32 dev vmbr0 done

sleep 1

echo 1 > /proc/sys/net/ipv4/conf/all/proxy_arp echo 1 > /proc/sys/net/ipv6/conf/default/proxy_ndp

sysctl -w net.ipv4.ip_forward=1 sysctl -w net.ipv6.conf.all.forwarding=1

Save.

📴 Step 4: Create cleanup script

Create:

nano /etc/wireguard/down.sh

Paste:

#!/bin/bash

for ip in {113..117}; do ip route del 5.231.32.$ip/32 dev vmbr0 ip route del 5.231.32.$ip/32 dev vmbr0 table 11 ip rule del from 5.231.32.$ip/32 table 11 prio 1 done

sleep 2

echo 0 > /proc/sys/net/ipv4/conf/all/proxy_arp echo 0 > /proc/sys/net/ipv6/conf/default.proxy_ndp

Save.

🔐 Step 5: Make scripts executable

chmod +x /etc/wireguard/up.sh chmod +x /etc/wireguard/down.sh

🌐 Step 6: Make forwarding persistent after reboot

Create:

nano /etc/sysctl.d/99-wireguard.conf

Add:

net.ipv4.ip_forward=1 net.ipv4.conf.all.proxy_arp=1 net.ipv6.conf.all.forwarding=1 net.ipv6.conf.default.proxy_ndp=1

Apply:

sysctl --system

🚀 Step 7: Enable WireGuard at boot

systemctl enable --now wg-quick@wg0

Check:

systemctl status wg-quick@wg0

Check routing:

ip rule

ip route show table 11

✅ Done

Your public IPs will now keep routing after:

• Proxmox reboot
• WireGuard restart
• Server restart

VM settings:

IP: 5.231.32.xxx/24

Gateway: 5.231.32.1

LXC settings:

IP: 5.231.32.xxx/32

Gateway: 5.231.32.1