There are various options for how Horizon can handle the UX problems
associated with adding additional domains. Making it a part of the URL
is one which could be supported, but I’m not inclined to make that the
only method. The implementation details can be hashed out when we get
there.
I am more concerned about the experience for CLI/API users; adding
more parameters they have to pass is quite unfriendly. And I have to
say that Keystone’s track record for handling “default” options has
been quite poor (see “default tenant”). The mixed support for lookups
via ID vs. name is also a mess. There needs to be consistency around
what is unique and in what scope (which is where this thread started).
So far I haven’t heard a concrete answer on that.
For example, if tenants uniqueness is scoped to a domain, and lookups
via tenant name are possible, and there’s a default domain… well
haven’t you just painted yourself into a corner where tenant names in
the default domain must be unique while names in any other domain do
not? It’s these kinds of issues that need to really be thought through.
-Gabriel
*From:*openstack-bounces+gabriel.hurley=nebula.com@xxxxxxxxxxxxxxxxxxx
<mailto:openstack-bounces+gabriel.hurley=nebula.com@xxxxxxxxxxxxxxxxxxx>
[mailto:openstack-bounces+gabriel.hurley=nebula.com@xxxxxxxxxxxxxxxxxxx <mailto:nebula.com@xxxxxxxxxxxxxxxxxxx>]*On
Behalf Of*Adam Young
*Sent:*Friday, October 26, 2012 4:19 PM
*To:*Henry Nash
*Cc:*OpenStack Development Mailing List; openstack@xxxxxxxxxxxxxxxxxxx
<mailto:openstack@xxxxxxxxxxxxxxxxxxx> (openstack@xxxxxxxxxxxxxxxxxxx
<mailto:openstack@xxxxxxxxxxxxxxxxxxx>)
*Subject:*Re: [Openstack] [keystone] Domain Name Spaces
On 10/26/2012 07:17 PM, Henry Nash wrote:
So to pick up on a couple of the areas of contention:
a) Roles. I agree that role names must stay globally unique. One
way of thinking about this is that it is not actually keystone
that is creating the "role name space" it is the other services
(Nova etc.) by specifying roles in their policy files. Until
those services support domain specific segmentation, then role
names stay global.
b) Will multi-domains make it more complicated in terms of
authorisation - e.g. will the users have to input a Domain Name
into Horizon the whole time? The first thing I would say is that
if the cloud administrator has create multiple domains, then the
keystone API should indeed require the domain specification.
However, that should not mean it should be laborious for a
Horizon user. In the case where a Cloud Provider has created
domains to encapsulate each of their customers - then if they want
to let those customer use horizon as the UI, then I would think
they want to be able to give each customer a unique URL which will
point to a Horizon that "knows which domain to go to".
Yes, I think that this is the solution. It will involve HTTPD virtual
hosts, and horizon can then get an additional config parameter
"keystone_domain" as part of the wsgi config.
Maybe the url contains the Domain Name or ID in the path, and Horizon
pulls this out of its own url (assuming that's possible) and hence the
user is never given an option to chose a domain. A Cloud Admin would
use a "non domain qualified url" to get to Horizon (basically as it is
now) and hence be able to see the different domains. Likewise, in the
case of where the Cloud Provider has not chosen to create any
individual domains (and is just running the cloud in the default
domain), then the "non domain qualified url" would be used to a
Horizon that only showed one, default domain and hence no choice is
required.
Henry
On 26 Oct 2012, at 17:31, heckj wrote:
Bringing conversation for domains in Keystone to the broader mailing
lists.
On Oct 26, 2012, at 5:18 AM, Dolph Mathews <dolph.mathews@xxxxxxxxx
<mailto:dolph.mathews@xxxxxxxxx>> wrote:
I think this discussion would be great for both mailing lists.
-Dolph
On Fri, Oct 26, 2012 at 5:18 AM, Henry Nash <henry.nash@xxxxxxx
<mailto:henry.nash@xxxxxxx>> wrote:
Hi
<Not sure where best to have this discussion - here, as a comment
to the v3api doc, or elsewhere - appreciate some guidance and will
transfer this to the right place>
At the Summit we started a discussion on whether things like user
name, tenant name etc. should be globally unique or unique within
a domain. I'd like to widen that discussion to try and a) agree a
direction, b) agree some changes to our current spec. Here's my
view as an opening gambit:
- When a Keystone instance is first started, there is only one,
default, Domain. The Cloud Provider does not need to create any
new domains, all projects can exist in this default domain, as
will the users etc. There is one, global, name space. Clients
using the v2 API will work just fine.
+1
Very much what we were thinking for the initial implemenation and
rollout to make it backwards "compatible" with the V2 (non-domain)
core API
- If the Cloud Provider wants to provide their customers with
regions they can administer themselves and be self-contained, then
they create a Domain for each customer. It should be possible for
users/roles to be scoped to a Domain so that (effectively)
administrative duties can be delegated to some users in that
Domain. So far so good - all this can be done with the v3 API.
Not clear on if you're referring to endpoint regions, or just
describing domain isolation?
I believe you're describing the key use cases behind the domains
mechanism to begin with - user and project partitioning to allow for
administration of those to be clearly "owned" and managed appropriately.
- We still have work to do to make sure items in other OS projects
that reference tenants (e.g. Images) can take a Domain or Project
ID, but we'll get to that soon enough
Everything will continue to work with projects, but once middleware
starts providing a DOMAIN_ID and DOMAIN_NAME to the underlying
service, it'll be up to them to take advantage of it. Images per
domain is an excellent example use case.
- However, Cloud Providers want to start enabling enterprise
customers to run more and more of the workloads in OpenStack
clouds - over and above, the smaller sized companies that are
doing this today. For this to work, the encapsulation of a
Domain need, I think, to be able to be stricter - and this is
where the name space comes into play. I think we need to
allow for a Domain to have its own namespace (i.e. users,
roles, projects etc.) as an option. I see this as a first
step to allowing each Domain to have its own AuthZ/N service
(.e.g external ldap owned and hosted by the customer who will
be using the Domain)
Implementation:
- A simplistic version would just allow a flag to specified on
Domain creation that said whether this a "private" or "shared"
Domain. Shared would use the current global name space (and
probably be the default for compatibility reasons).
I like the direction of this -- need to digest implications :)
I like the idea conceptually - but let's be clear on the implications
to the end users:
Where we're starting is preserving a global name space for project
names and user names. Allowing a mix of segregated and global name
spaces imposes a burden of additional data being needed to uniquely
place authentication and authorization.
We've been keeping to 2 key pieces of info (username, password) to get
authenticated - and then (via CLI or Horizon dashboard) you can choose
from a list of protential projects and carry on. In most practical
circumstances, any user working primarily from the CLI is already
providing 3-4 pieces of information:
* username
* password
* tenant name
* auth_url
to access and use the cloud.
By allowing domains to be their own namespaces, we're adding another
element that will be absolutely required to identify the person
authenticating:
* domain name
implying a cascade of changes to the user experience all the way down
through horizon.
- A more flexible approach would be to allow the specification of
where the various sub-services of Keystone (e.g. AuthN/Z, Service
Catalogue, Resources (i.e Users, Projects)) are hosted. The
defaults would all point back to the default domain (i.e. are
global and shared), but instead could be specified as "self" (I.e.
the new Domain), or, in the future, some other external location,
e.g. for a remote ldap.
- As an aside, this multi-name space model could also allow the
Cloud Provider their own name space, separate from their customers
- i.e. they will have a need to create admins who can just create
domains and on-board customers into those domains. These users &
roles could exist in the default domain, while all the customers'
users/roles exist solely within their own domains.
- One potential problem I do see is with roles. Today, the role
name is, if I understand it correctly, a kind of shared secret
between, other services and Keystone - e.g. it is the actual name
of a given role, say "ProjectAdmin" , that must match in, say, the
Nova policy file and the role assignment in Keystone (please
correct me if I have this wrong).
You're 100% correct.
How would that work if the role names were not unique across Domains?
Not that we would want admins to ever see Role ID's, or edit policy
files with role ID's, but they provide a potential solution.
The different role names would need to be accounted for in the policy
files the way they're set up today - the enforcement there is all at
the service level. There's no current provision for evaluating policy
differently based on domain. While that's possible, it sounds like a
tremendous cascade of additional complication, as the policy, and
roles, are all set up and managed by deployers.
I think this might be an interesting addition in the future, but want
to keep the initial implementation and roll-out of the policy
mechanisms and domains consistent and simple for a first roll-out
iteration.
What is the desired functionality for a Cloud Provider wanting
to give their enterprise customers this level of flexibility -
will they have dedicated Nova endpoints anyway? Sounds too
rigid. This might tie into another bp we are working on at
IBM in terms of using Availability zones to allow Cloud
Providers to divide up their compute resources in a more
flexible way.
- Finally, I wanted to raise the subject of whether we should
make it a goal to remain compatible with the v2 API/once the
cloud provider starts creating additional domains/.
Joe and I briefly discussed this at the summit. As a migration to
v3, we'd obviously be creating the default domain and mapping all
existing users/projectse/etc to it. I'd be fine if the v2
implementation ONLY interacted with resources in that default
domain; i.e. if you want to use domains, upgrade to a v3 client.
As stated above, if just the default domain is being used,
then fine. And while I agree that, technically, the v2 API
should still work with the above if all the other domains
point back to the default domain for their sub-services - it
feels overly flexible (and maybe wrong conceptually) to
support v2 semantics across a multi-domain installation.
+1
Interested in everyone else's view.
Henry
