Need to document migration path from Havana to Icehouse

[Tom Fifield]

We need to document the process of migrating/upgrading a havana deployment to icehouse, with minimal-to-no downtime.

[chandan kumar (chkumar246)]

@Tom, will you please some more input on this bug in order to solve this?

[Tom Fifield (fifieldt)]

Take an existing Havana installation, with some VMs running. Turn it into an Ice-House installation, without killing those VMs.

Document this.

To solve this bug: requires a _lot_ of deep technical work, testing and analysis to determine how to do this.

[Tom Fifield (fifieldt)]

This process should use the "upgrade_levels" settings in nova.conf

[Matt Kassawara (ionosphere80)]

I suspect this should wait until after the release of Icehouse.

[Summer Long (slong-g)]

Current notes are here: https://wiki.openstack.org/wiki/ReleaseNotes/Icehouse#General_Upgrade_Notes

[Tom Fifield (fifieldt)]

Icehouse API cell can work with havana compute cells.

[Tom Fifield (fifieldt)]

 havana glance api can talk to a icehouse registry

[Stephen Gordon (sgordon)]

Discussion of Havana->Icehouse for Cells is here:

http://lists.openstack.org/pipermail/openstack-dev/2014-April/033376.html

[Andreas Jaeger (jaegerandi)]

Patch at https://review.openstack.org/91626