Use force=True for os-brick disconnect during delete

The 'force' parameter of os-brick's disconnect_volume() method allows
callers to ignore flushing errors and ensure that devices are being
removed from the host.

We should use force=True when we are going to delete an instance to
avoid leaving leftover devices connected to the compute host which
could then potentially be reused to map to volumes to an instance that
should not have access to those volumes.

We can use force=True even when disconnecting a volume that will not be
deleted on termination because os-brick will always attempt to flush
and disconnect gracefully before forcefully removing devices.

Closes-Bug: #2004555

Change-Id: I3629b84d3255a8fe9d8a7cea8c6131d7c40899e8

1 files changed, 59 insertions, 0 deletions

diff --git a/doc/source/admin/configuration/service-user-token.rst b/doc/source/admin/configuration/service-user-token.rst
new file mode 100644
index 0000000000..740730af1d
--- /dev/null
+++ b/doc/source/admin/configuration/service-user-token.rst
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+.. _service_user_token:
+
+===================
+Service User Tokens
+===================
+
+.. note::
+
+   Configuration of service user tokens is **required** for every Nova service
+   for security reasons. See https://bugs.launchpad.net/nova/+bug/2004555 for
+   details.
+
+Configure Nova to send service user tokens alongside regular user tokens when
+making REST API calls to other services. The identity service (Keystone) will
+authenticate a request using the service user token if the regular user token
+has expired.
+
+This is important when long-running operations such as live migration or
+snapshot take long enough to exceed the expiry of the user token. Without the
+service token, if a long-running operation exceeds the expiry of the user
+token, post operations such as cleanup after a live migration could fail when
+Nova calls other service APIs like block-storage (Cinder) or networking
+(Neutron).
+
+The service token is also used by services to validate whether the API caller
+is a service. Some service APIs are restricted to service users only.
+
+To set up service tokens, create a ``nova`` service user and ``service`` role
+in the identity service (Keystone) and assign the ``service`` role to the
+``nova`` service user.
+
+Then, configure the :oslo.config:group:`service_user` section of the Nova
+configuration file, for example:
+
+.. code-block:: ini
+
+   [service_user]
+   send_service_user_token = true
+   auth_url = https://104.130.216.102/identity
+   auth_strategy = keystone
+   auth_type = password
+   project_domain_name = Default
+   project_name = service
+   user_domain_name = Default
+   username = nova
+   password = secretservice
+   ...
+
+And configure the other identity options as necessary for the service user,
+much like you would configure nova to work with the image service (Glance) or
+networking service (Neutron).
+
+.. note::
+
+   Please note that the role assigned to the :oslo.config:group:`service_user`
+   needs to be in the configured
+   :oslo.config:option:`keystone_authtoken.service_token_roles` of other
+   services such as block-storage (Cinder), image (Glance), and networking
+   (Neutron).