[lug] IPV6 clouds [was Re: cloud recommendation]

Rob Nagler nagler at bivio.biz
Tue Nov 2 11:31:50 MDT 2010

David L. Anselmi writes:
> Are clouds using IPv6 yet?

You get an ipv4 address.

> Do most instances get public addresses?

Yes, there would be no way to ssh into them otherwise.  At the same
time, they give you an internal address on the interface.  They offer
load balancing so one would assume that you wouldn't need public
addresses for those.  You'd only have one public IP address (I'm
guessing), and it would route dynamically to the internal address all
instances have so when you'd ssh into those hosts (if you did
directly) then you'd have to ssh to internal addresses to get to a
specific instance.  

Also, I am dealing with some spambox issues, and I was wondering if
you could set up PTR records.  Turns out you can:


Don't know if this is public.  Here's the email which discusses PTR


> Does that increase the shortage of v4 addresses?

I didn't have to do anything special to get the public address so I
would guess this is going to put some pressure on the networks,
because people are going to bring instances up and down.  However, the
load balancers will help.  Also, you get a bunch of services which are
not in your instance's IP address space.  These services (SAN,
SimpleDB, etc.) are natted.  My guess is that you'll need fewer public
addresses than you would otherwise as a result.

Another factor is that you get access to a huge number of machines on
their internal net.  You might rely on their redundancy, and therefore
you could backup over the backnet only.  Right now, we've got machines
in FRII and ViaWest for redundancy.  That wouldn't be necessary and
frankly, it's probably not as good as AWS's redundancy -- if the
Telecom Hotel in Denver goes down, we're screwed.


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