Package updates and charm responsibilities

Stuart Bishop stuart.bishop at
Thu Apr 10 11:00:14 UTC 2014

On 10 April 2014 17:42, John Meinel <john at> wrote:
> All hooks are run sequentially (we explicitly take out a lock across all
> hooks that want to run on a machine), just so that charms can do whatever
> they want with apt without stepping on each other's toes.
> I would think "install" is the most likely hook to actually do update and
> install. I'm not sure about a charm ever doing "upgrade" since that would
> upgrade other packages, right?

Right. I'm wondering if that is the responsibility of the charm, or of
other management systems like Landscape or configuring unattended
security updates.

At the moment I do have a charm that does an upgrade, and it does
upgrade everything. I suspect I should remove that line.

> There isn't a process in juju today that does regular "keep my machines up
> to date" but you do have "juju run sudo apt-get update" if you want to do it
> manually.

There is 'upgrade-charm'. I could argue that upgrade-charm should do a
full update, so the new version of the charm is running with all the
dependencies it was tested with. But I can argue the other way too :D

Stuart Bishop <stuart.bishop at>

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