* Add a connection-string based workflow to MicroStack;
* microstack add-compute command can be run at the Control node in
order to generate a connection string (an ASCII blob for the user);
* the connection string contains:
* an address of the control node;
* a sha256 fingerprint of the TLS certificate used by the clustering
service at the control node (which is used during verification
similar to the Certificate Pinning approach);
* an application credential id;
* an application credential secret (short expiration time, reader
role on the service project, restricted to listing the service
catalog);
* a MicroStack admin is expected to have ssh access to all nodes that
will participate in a cluster - prior trust establishment is on
them to figure out which is normal since they provision the nodes;
* a MicroStack admin is expected to securely copy a connection string
to a compute node via ssh. Since it is short-lived and does not
carry service secrets, there is no risk of a replay at a later time;
* If the compute role is specified during microstack.init, a
connection string is requested and used to perform a request to the
clustering service and validate the certificate fingerprint. The
credential ID and secret are POSTed for verification to the
clustering service which responds with the necessary config data
for the compute node upon successful authorization.
* Set up TLS termination for the clustering service;
* run the flask app as a UWSGI daemon behind nginx;
* configure nginx to use a TLS certificate;
* generate a self-signed TLS certificate.
This setup does not require PKI to be present for its own purposes of
joining compute nodes to the cluster. However, this does not mean that
PKI will not be used for TLS termination of the OpenStack endpoints.
Control node init workflow (non-interactive):
sudo microstack init --auto --control
microstack add-compute
<the connection string to be used at the compute node>
Compute node init workflow (non-interactive):
sudo microstack init --auto --compute --join <connection-string>
Change-Id: I9596fe1e6e5c1a325cc71fd3bf0c78b660b9a83e