[Swan-dev] simplifying a kvm upgrade

[Andrew Cagney]

Hugh used 'make kvm-purge' expecting it to force the VMs to be
upgraded, but it didn't.  Should it.

This is how things currently work:

make kvm-clean:
zaps the local directory's test and build domains; 'make kvm-install'
will then rebuild those domains from 'clone' and since 'clone' isn't
modified the VMs don't get upgraded
I think this is correct behaviour.  Having 'make kvm-clean' requre
network access to upgrade random RPMs would be confusing.

make kvm-purge:
in addition to kvm-clean, zap's the local directory's 'clone' domain;
'make kvm-install' builds 'clone' from$(KVM_OS)base before building
the test domains and since $(KVM_OS)base isn't modified the VMs don't
get upgraded

make kvm-demolish:
since this also deletes $(KVM_OS)base it forces an upgrade, but seems
like overkill I wonder if it should be called kvm-distclean, ...

I'm wondering if the targets 'make kvm-upgrade' and
'kvm-upgrade-base-domain' should be dumped and instead, when the clone
domain is being created, also do an upgrade.

- this means that 'make kvm-purge' will do what Hugh expected
- less make targets which is typically better
- it doesn't affect the normal workflow using 'make kvm-clean'

but also:

- creating the 'clone' domain requires access to the network so is slower
- getting multiple directories in sync gets harder

thoughts,
Andrew