Re: AWS issues with 172.0.0.0/12

[Javier J <javier () advancedmachines us>]

Very strange ATT would put end users on an RFC 1918 block unless they were
doing NAT to the end user.
If they were doing NAT, I would expect CGNAT in the 100.something or other
range.


On Thu, Oct 10, 2019, 11:07 AM Mehmet Akcin <mehmet () akcin net> wrote:

> Yes
>
> On Wed, Oct 9, 2019 at 20:46 Javier J <javier () advancedmachines us> wrote:
>
> > I'm just curious, was the ip in the RFC 1918 172.16.0.0/16 range?
> >
> > https://tools.ietf.org/html/rfc1918
> >
> >
> >
> > On Mon, Oct 7, 2019 at 6:01 PM Mehmet Akcin <mehmet () akcin net> wrote:
> >
> > > To close the loop here (in case if someone has this type of issue in the
> > > future), I have spoken to AT&T instead of trying to work it out with AWS
> > > Hosted Vendor, Reolink.
> > >
> > > AT&T Changed my public IP, and now I am no longer in that 172.x.x.x
> > > block, everything is working fine.
> > >
> > > mehmet
> > >
> > > On Thu, Oct 3, 2019 at 2:54 PM Javier J <javier () advancedmachines us>
> > > wrote:
> > >
> > > > Auto generated VPC in AWS use RFC1819 addresses. This should not
> > > > interfere with pub up space.
> > > >
> > > > What is the exact issue? If you can't ping something in AWS chances are
> > > > it's a security group blocking you.
> > > >
> > > >
> > > >
> > > > On Tue, Oct 1, 2019, 7:00 PM Jim Popovitch via NANOG <nanog () nanog org>
> > > > wrote:
> > > >
> > > > > On October 1, 2019 9:39:03 PM UTC, Matt Palmer <mpalmer () hezmatt org>
> > > > > wrote:
> > > > > > On Tue, Oct 01, 2019 at 04:50:33AM -0400, Jim Popovitch via NANOG
> > > > > > wrote:
> > > > > > > On 10/1/2019 4:09 AM, Christopher Morrow wrote:
> > > > > > > > possible that this is various AWS customers making
> > > > > > iptables/firewall mistakes?
> > > > > > > >    "block that pesky rfc1918 172/12 space!!"
> > > > > > >
> > > > > > > AWS also uses some 172/12 space on their internal network (e.g. the
> > > > > > network
> > > > > > > that sits between EC2 instances and the AWS external firewalls)
> > > > > >
> > > > > > Does AWS use 172.0.0.0/12 internally, or 172.16.0.0/12?  They're
> > > > > > different
> > > > > > things, after all.
> > > > >
> > > > > I don't know their entire operations, but they do use some
> > > > > 172.16.0.0/12
> > > > > addresses internally. And yes, that is very different than 172/12,
> > > > > sorry
> > > > > for the confusion.
> > > > >
> > > > > -Jim P.
> > > > >
> > > > > --
> Mehmet
> +1-424-298-1903