On 4/8/20 2:42 PM, Drew Weaver wrote:
Hello,
I’ve noticed over the past couple of weeks that some hosts on a network
I manage appear to be trying to reach hosts in this network 100.114.128.0/24
It’s an IANA reserved block but I’m really not sure what it’s used for.
I just notice it keeps coming up but it doesn’t have a route.
Has anyone else been seeing this?
This is part of the RFC6598 space for carrier-NAT deployments. If
you're seeing traffic inbound to your network to those addresses,
someone's presumably got a default toward you and a hole in their
internal routing table. If you're seeing traffic outbound toward those
addresses, some of your customers have somehow picked up a configuration
expecting some sort of service there.
Inbound traffic toward your network from or to those addresses is
effectively a bogon. Outbound traffic from/to those addresses means you
have a misconfiguration somewhere (presumably unintentional and perhaps
some poorly behaved automatic config on a CPE).
--
Brandon Martin
