maas-devel team mailing list archive

[Andres Rodriguez <andres.rodriguez@xxxxxxxxxxxxx>]

On Thu, May 1, 2014 at 5:05 PM, Gavin Panella
<gavin.panella@xxxxxxxxxxxxx>wrote:

> With reference to bug 1314267 [1] and bug 1274499 [2], we have a problem
> where ISC DHCPD, when running low on unused addresses, hands out IPs
> that are marked as reserved for a different host, or addresses that
> appear to already be in use.
>
> We've discussed allocating a smaller window of a cluster's overall
> network range to dynamic allocation, but this is somewhat complex, and
> can be swamped by, for example, LXC containers using DHCP to obtain IP
> addresses for their bridged interfaces.
>
> However, each cluster is meant to be on its own layer-2 subnet, so every
> cluster could reasonably hand out link local addresses [3] from a (very
> large) dynamic pool (and every cluster could use the same range, because
> they're link-local and won't overlap). With some changes to MAAS [4]
> this would be sufficient for enlistment and commissioning.
>
> Then, when a machine is allocated to a user, an address can be chosen
> from the cluster's configured network, and assigned statically to the
> node by MAAS. This could be configured during node installation, or
> added as a static host entry to the DHCP server (as now, except outside
> of the dynamic pool), or both.
>

Why not making the static the addresses that have already been assigned
during enlistment/commissioning ? It seems to me that when the
commissioning process happens, the node already know what's its IP address.
Why not making an static mapping at that stage?

>
> LXC containers would come up and obtain link-local addresses, which is
> not going to be terribly useful. MAAS would have to provide an API by
> which a node could obtain additional IP addresses. Juju, for example,
> would be forced to obtain new IP addresses from MAAS when creating new
> containers. [5]
>
> What do you think?
>
>
> [1] MAAS dhcpd will re-issue leases for nodes
> <https://bugs.launchpad.net/maas/+bug/1314267>
>
> [2] (dhcp lease rollover causes loss of access to managment IP
> <https://bugs.launchpad.net/ubuntu/+source/maas/+bug/1274499>
>
> [3] http://en.wikipedia.org/wiki/Link-local_address
>
> [4] Nodes are given a URL that points back to the region from which to
> obtain their preseed, and they report commissioning results direct to
> the region too. These would have to change to either be proxied via or
> handled by the cluster.
>
> [5] This API could be extended so that a user could obtain IP addresses
> for use as VIPs by multiple nodes. These wouldn't be deallocated as long
> as one or more of those nodes is still allocated.
>
> --
> Mailing list: https://launchpad.net/~maas-devel
> Post to     : maas-devel@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~maas-devel
> More help   : https://help.launchpad.net/ListHelp
>



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