Marc Meszaros MarcMeszaros

Fix for OPNsense multiple IPv6 Gateway Router Advertisements

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This script automatically detects and sets the correct IPv6 default gateway when multiple Router Advertisements are present on your WAN interface and OPNsense picks the wrong one as the default gateway. This results it routing issues and loss of connectivity to the internet.

The Problem

Some network setups (particularly fiber connections with ONTs) may send multiple Router Advertisements:

ONT/Bridge device (wrong): Low preference, lifetime: 0s (explicitly says "don't use me")

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	#!/usr/bin/env python
	import argparse
	import sys
	from subprocess import call, check_output

	# version check
	if sys.hexversion < 0x02070000:
	sys.exit('Python 2.7 or newer is required to run this program.')