On Wed, Apr 10, 2019 at 6:30 PM John Fulton <johfulto@redhat.com> wrote:
In the Ceph case ceph-ansible has playbooks to correctly handle the scale down of different ceph services, e.g. delete a monitor [1] or delete an OSD [2]. The process would be to generate a ceph-ansible inventory, e.g. the same way we do when we scale up [3], and then execute one of those playbooks with that inventory. Examples of running these playbook are in Seb's blog [4].
This would be a great feature to have because if you don't tell the Ceph cluster that a node is not part of it anymore, then it will want to find it and not be happy if you just delete the node. It's better to tell the ceph cluster not to worry about a particular node anymore by running one of these playbooks before the node is deleted.
So if I'm not mistaken, these tasks need to run within the mistral_executor on the Undercloud against a generated ceph-ansible inventory. Which means, no tasks are run on hosts on local mode. Let me know if I'm wrong, I'll make sure this is working fine for the scale tasks. -- Emilien Macchi