Nova Cell support

Registered by Nick Barcet

Investigate Nova Cell support, if it lands early enough

Blueprint information

Nick Barcet
Julien Danjou
Series goal:
Not started
Milestone target:
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Completed by
gordon chung

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Cells code isn't finished yet, several critical patches are still missing in Nova.

As for the support needed, from what I saw in the code, all we may need to do in Ceilometer is to add another metadata field called "cell_name" on our side that's copied from the metadata included in the notifications payload (like we already for vcpu, root_gb, etc).

The solution described by NIck at the Havana summit is to add a cell parameter in Ceilometer and to use it to add a cell tag into the instances metadata. There seems to be no other way to do that than to configure Ceilometer with this information.

It will also require to be able to define two set of RPC hosts: one set of RPC server we use to collect information from the child cell and another set were we publish agregated result on the top cell.

sorrison > I'd like to help with this. We have a large cells installation in production. We have ceilometer in our test environment and for us the main thing is that we need to be able to define 2 RPC hosts to get the messages from compute level RPC server to API level RPC server. I'm not that familiar with ceilometer codebase yet but have plenty of kit to test stuff on in a production like system (aka not devstack).


Is there still a chance of this making Havana ? At CERN, we're using cells and this functionality would be very welcome.

  It has been started, you can hijack it if you want -- jd

closing this as we don't use bp. here's the first patch: - gordc(2017-12)


Work Items

Work items:
Waiting for cell to be delivered in nova: INPROGRESS

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