DoD IP Space

Sabri Berisha sabri at
Thu Feb 11 20:52:51 UTC 2021

----- On Feb 11, 2021, at 9:15 AM, Eric Kuhnke <eric.kuhnke at> wrote: 


You're right and wrong. 

> You don't, you wastefully assign a /24 to every unique thing that you think
> needs an internal management IP block (even if there's 5 things that answer
> pings there),

Reword that to: in the late 1990s, someone took an ICND course and decided
that assigned a /24 as a minimum for each subnet was fine as they would never
run out of RFC1918 space. 

Today, the current network owner is stuck with that inherited problem. 

> and decide it's too much work to renumber things.

Reword that to: and management decides that they are not going to fund a
renumbering project as they have other priorities. (that's how work gets
funded in every large org that I've worked for) 

> Easy for a big ISP that's also acquired many small/mid-sized ISPs to run out of
> v4 private IP space that way.

Not just ISPs. Plenty of decades old enterprises.

Mark Tinka wrote:

> Let's not normalize the sustenance of IPv4 in 2021, in the real world.

Our opinions don't matter to the PHBs whos bonuses rely on features delivered.

The only time that I got some serious attention with regards to this matter was
when my manager and I took it three layers up and warned them that we were
about to run out of RFC1918 space unless drastic measures were taken. They were,
but now how we wanted: they forced other groups to return unused allocations.
Now we had half of 10/8 back, and deployment of new pods could resume...

Problem "solved".

I get really sad when people bicker on this list about who is at fault. The
purity fundamentalists complain that realists have run out of RFC1918 due to
their poor decisions, while in 99% of the cases it's a result of decisions made
long ago by their predecessors. The true enemy here is mid-level management 
that refuses to prioritize deployment of IPv6.

What we should be discussing is how best to approach that problem. It's where
ops and corporate politics overlap.



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