Skip to main content


Zscaler seeing a user has an IP in 100.0.0.0/8 tells me that wont work because that's a Zscaler internal IP.

Of course, the user's ISP is misusing CGNAT and also claiming IANA reserved IPs are theirs.

Abolish legacy IP

@The Psychotic Network Ferret the problem was that neither group using 100.6.0.0/16 *owned* it. Both of them were using it for extra IPv4 space.

And I've been a ISP grunt, I know we want IPv4 to die, but there's some ISPs that have bonkers IPv4 stacks and massive CGNATs without a whisper of IPv6