Persistence on UCG fiber

[00ihsan]

I asked chat gpt and this is what it says

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KPN IPTV on UniFi UCG — Persistent Configuration (English Explanation)

KPN IPTV requires several network functions that are not supported in the UniFi user interface on UCG devices.
While you can create VLAN 4 in the UI, the essential multicast routing components cannot be configured there.

What the UniFi UI can configure

Creation of VLAN 4 (KPN IPTV VLAN)

Port profiles / separate IPTV networks

IGMP Snooping on UniFi switches

These settings are preserved through provisioning.

Missing components (must be added manually)

KPN IPTV requires the following functions, which UniFi does not expose in the UI:

IGMP Proxy

Upstream interface = WAN

Downstream interface = VLAN 4

Firewall rules for multicast video traffic

Typically UDP 1234–1237

Allowing multicast from the ISP → IPTV network

Static route

213.75.0.0/16 → IPTV interface (VLAN 4)

Required for KPN’s multicast domain

Because these features are not available in the UI, they must be injected at the OS layer.

Permanent Solution: Application Scripts

UDM/UXG devices support persistent on-boot scripts.
Any shell script placed under:

/data/on_boot.d/

is executed automatically at startup and is not overwritten by the UniFi controller.

Example:

/data/on_boot.d/10-kpn-iptv.sh

This makes KPN IPTV fully persistent without modifying system files, and without relying on outdated USG methods such as config.gateway.json.

What we need from the UXG

To generate a final working IPTV configuration script, we need two interface names:

1. WAN interface name

Common examples on UXG Fiber:

eth9

eth10

wan

Can be verified using:

ip a

2. IPTV (VLAN 4) interface name

Typically one of:

br4

eth1.4

vlan4

This depends on how VLANs are managed internally by the UXG model.

Summary

UniFi UI cannot configure IGMP Proxy or multicast routing.

IPTV requires IGMP Proxy, firewall rules, and static routes.

These must be set using a persistent on-boot application script.

This script is fully supported and survives provisioning and firmware updates.

We only need the WAN and VLAN-4 interface names to generate the final script.

[00ihsan]

example script

#!/bin/sh

KPN IPTV persistent configuration for UniFi UDM/UXG

Replace WAN_IFACE and IPTV_IFACE with actual interface names.

WAN_IFACE="eth9"
IPTV_IFACE="br4"

Enable IP forwarding

sysctl -w net.ipv4.ip_forward=1

Kill existing igmpproxy if running

killall -q igmpproxy

Create temporary igmpproxy config

cat </tmp/igmpproxy.conf
quickleave
phyint $WAN_IFACE upstream ratelimit 0 threshold 1
phyint $IPTV_IFACE downstream ratelimit 0 threshold 1
EOF

Start igmpproxy

igmpproxy /tmp/igmpproxy.conf

Firewall rules (allow multicast traffic)

iptables -I FORWARD -i $WAN_IFACE -o $IPTV_IFACE -j ACCEPT
iptables -I FORWARD -i $IPTV_IFACE -o $WAN_IFACE -j ACCEPT
iptables -I INPUT -p igmp -j ACCEPT
iptables -I INPUT -p udp --dport 1234:1237 -j ACCEPT

Static route for KPN multicast domain

ip route replace 213.75.0.0/16 dev $IPTV_IFACE

exit 0

save in /data/on_boot.d/10-kpn-iptv.sh