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Does tripleo overcloud contain only vm?

asked 2014-03-11 20:09:14 -0500

xu-haiwei gravatar image

updated 2014-03-12 03:14:55 -0500

I am still confused about tripleo's architecture even reading the wiki.

I am confused about:

  • Does undercloud contain only baremetal vm?
  • Does overcloud contain only vm(without baremetal vm)?
  • I think in undercloud heat and heat-template are used to deploy overcloud, if overcloud contains baremetal vm, can heat deploy that?

My understanding is :

  • seed cloud: an openstack environment with nova-baremetal service running.
  • undercloud: a baremetal node deployed by the seed cloud with heat in it. Configure with os-apply-config, os-refresh-config and os-collect-config, and create an openstack environment with heat-template.
  • overcloud: This cloud is running on the undercloud on the same baremetal machine. This cloud is created by heat using the heat-template, so there should be no baremetal node in overcloud, and only KVM ,Xen or else.

Now, I am confused because of the information on this site.

Does the 'Overcloud' in this site equals to the overcloud I said? I think it points to the undercloud.

Thank you.

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Yes, I mean when deploying the overcloud, do you have to deploy it on the baremetal machine? I have got the answer from the PTL Robert Collins, the overcloud is hosted on the baremetal machine, and on the overcloud we can create Kvm, Xen etc. The undercould and overcloud are on the different nodes.

xu-haiwei gravatar imagexu-haiwei ( 2014-03-13 21:59:33 -0500 )edit

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answered 2014-03-12 12:41:29 -0500

OverCloud is a new cloud provisioned from under cloud. Once overcloud is up, you can even kill the undercloud

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Part of this is untrue. The overcloud machines need the undercloud for DHCP, DNS, routing, and configuration updates.

SpamapS gravatar imageSpamapS ( 2014-05-07 03:17:35 -0500 )edit

answered 2014-03-17 14:18:17 -0500

lbesselink gravatar image

The undercloud is used to deploy one or more overclouds.

It has nothing directly to do with the hardware the overcloud runs on.

While the undercloud usually manages some of the bare metal hardware/installation, the overcloud could for example manage (other) pools of bare-metal hardware as well.

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Asked: 2014-03-11 20:09:14 -0500

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Last updated: Mar 17 '14