IPv6 Bogon Routes

Bogon routes or martian routes are the prefixes that should not be present in the global routing table simply because those prefixes are not really allocated to any organisation by the RIR. Like IPv4, we have a list of IPv6 bogon routes:

2001::/32 le 128: Teredo subnets
2001:db8::/32 le 128: Documentation
2002::/16 le 128: 6to4 subnets
2020:3030::/32 le 128: Local prefix
3ffe::/16 le 128: Old 6bone

Here’s the template prepared for Cisco routers to filter out those unwanted prefixes from your upstream. You can convert it to your preferred OS and use it accordingly.

CISCO

router bgp <your ASN>
 neighbor <neighbor’s IPv6 address> remote-as <neighbor’s ASN>
 address-family ipv6 unicast
  neighbor <neighbor’s IPv6 address> prefix-list v6in-filter in
!
ipv6 prefix-list v6in-filter permit 2001::/32
ipv6 prefix-list v6in-filter deny 2001::/32 le 128
ipv6 prefix-list v6in-filter deny 2001:db8::/32 le 128n
ipv6 prefix-list v6in-filter permit 2002::/16
ipv6 prefix-list v6in-filter deny 2002::/16 le 128
ipv6 prefix-list v6in-filter deny 2020:3030::/32 le 128
ipv6 prefix-list v6in-filter deny 3ffe::/16 le 128
ipv6 prefix-list v6in-filter permit 2000::/3 le 48
ipv6 prefix-list v6in-filter deny ::/0 le 128

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