maas-devel team mailing list archive

[Andres Rodriguez <andres.rodriguez@xxxxxxxxxxxxx>]

Hi Mark,

>
> The important attitude is to say "IP addresses are a resource that MAAS
> manages itself". So, rather than MAAS only providing services on the
> range we tell it to, MAAS needs to be able to provide services on all
> the OTHER IPs on the networks it is managing.
>
> By that I mean:
>
>  * DHCP for unmanaged machines ("my switch management IP is X.y.z.a")
>  * ability to reserve and release IPs for things like Landscape to use
>        ("Landscape has asked for these IPs on this network to statically
> configure")
>
> ... and DNS likewise.
>

Agreed! And this is where I believe we are moving towards (the latter, at
least).

>
> > 1. Having machines with pre-allocated addresses makes maintenance easier.
> > Nodes will always have a DNS/IP address mapping, allowing the
> administrator
> > to know IP addresses before hand, which eases maintenance.
>
> By "always" we mean "until a user decides to reassign the IP or remove
> the association". In other words, the principle is least surprise:
>
>  * if a machine is at an IP it stays there
>  * until a human says to do otherwise
>
> Make sense?
>

Correct! I also believe that it is up to the user to be able to re-assign
or remove the IP association .



>  >
> > Disadvantages
> >
> > 1. This is not a cloud-like approach.
> > 2. We will be using IP address of a network range even if machines are
> > powered off.
>
> Yes, I see this point, and I think it makes sense to have the ability to
> say that some machines or IP addresses are harvested automatically, for
> use in very large environments (so a human doesn't have to do the work).
>

> The problem we have, from a user experience point of view, is that most
> initial MAAS deployments are small, and if the behaviour of MAAS is
> surprising or unpredictable or awkward for those small deployments then
> they will never become BIG deployments :)


The good thing is that we now have places were we can test a larger
deployment and discover issues that we might not have been able to do so
otherwise. This is how we came across the initial issues that were the
driving force for this work.

>
> > 3. We could potentially allocate multiple IP's to a node, each one to a
> > different MAC addresses.
>
> Worse - multiple IPs to a single MAC address. Aliases are exactly that,
> and need to be supported.
>

Completely agree.

We have come across situations where we needed MAAS to provide DHCP for
different networks, in different network interfaces (Network A for NIC1,
Network B for NIC2). Allowing the user to assign 1 IP (and/or its aliases)
per NIC in MAAS, is something that would solve this requirement as well.

Thanks!
-- 
Andres Rodriguez
Engineering Manager, HWE Team
Canonical USA, Inc.