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Comment by 1970-01-01

7 months ago

Why is it harder to firewall them with IPv6? I seems this would be the easier of the two to firewall.

Manual banning is about the same since you just book /56 or bigger, entire providers or countries.

Automated banning is harder, you'd probably want a heuristic system and look up info on IPs.

IPv4 with NAT means you can "overban" too.

  • Why wouldn't something like fail2ban not work here? That's what it's built for and has been around for eons.

    • Fun part was that fail2ban had RCE vulnerability. So you were more secure not running it now it should be fixed but can you be sure?

I think they are suggesting the range of IPs to block is too high?

  • Allow -> Tarpit -> Block should be done by ASN

    • You probably want to check how many ips/blocks a provider announces before blocking the entire thing.

      It's also not a common metric you can filter on in open firewalls since you must lookup and maintain a cache of IP to ASN, which has to be evicted and updated as blocks still move around.

Maybe it’s easier to circumvent because getting a new IPv6 address is easier than with IPv4?