Deprecate the term "Ubernetes" in favor of "Cluster Federation" and "Multi-AZ Clusters"

3 files changed, 32 insertions, 29 deletions

diff --git a/federation-lite.md b/federation-lite.md
index eb326cb4..f9b1b741 100644
--- a/federation-lite.md
+++ b/federation-lite.md
@@ -34,25 +34,25 @@ Documentation for other releases can be found at
 
 # Kubernetes Multi-AZ Clusters
 
-## (a.k.a. "Ubernetes-Lite")
+## (previously nicknamed "Ubernetes-Lite")
 
 ## Introduction
 
-Full Ubernetes will offer sophisticated federation between multiple kuberentes
+Full Cluster Federation will offer sophisticated federation between multiple kuberentes
 clusters, offering true high-availability, multiple provider support &
 cloud-bursting, multiple region support etc.  However, many users have
 expressed a desire for a "reasonably" high-available cluster, that runs in
 multiple zones on GCE or availability zones in AWS, and can tolerate the failure
 of a single zone without the complexity of running multiple clusters.
 
-Ubernetes-Lite aims to deliver exactly that functionality: to run a single
+Multi-AZ Clusters aim to deliver exactly that functionality: to run a single
 Kubernetes cluster in multiple zones.  It will attempt to make reasonable
 scheduling decisions, in particular so that a replication controller's pods are
 spread across zones, and it will try to be aware of constraints - for example
 that a volume cannot be mounted on a node in a different zone.
 
-Ubernetes-Lite is deliberately limited in scope; for many advanced functions
-the answer will be "use Ubernetes (full)".  For example, multiple-region
+Multi-AZ Clusters are deliberately limited in scope; for many advanced functions
+the answer will be "use full Cluster Federation".  For example, multiple-region
 support is not in scope.  Routing affinity (e.g. so that a webserver will
 prefer to talk to a backend service in the same zone) is similarly not in
 scope.
@@ -122,7 +122,7 @@ zones (in the same region).  For both clouds, the behaviour of the native cloud
 load-balancer is reasonable in the face of failures (indeed, this is why clouds
 provide load-balancing as a primitve).
 
-For Ubernetes-Lite we will therefore simply rely on the native cloud provider
+For multi-AZ clusters we will therefore simply rely on the native cloud provider
 load balancer behaviour, and we do not anticipate substantial code changes.
 
 One notable shortcoming here is that load-balanced traffic still goes through
@@ -130,8 +130,8 @@ kube-proxy controlled routing, and kube-proxy does not (currently) favor
 targeting a pod running on the same instance or even the same zone.  This will
 likely produce a lot of unnecessary cross-zone traffic (which is likely slower
 and more expensive).  This might be sufficiently low-hanging fruit that we
-choose to address it in kube-proxy / Ubernetes-Lite, but this can be addressed
-after the initial Ubernetes-Lite implementation.
+choose to address it in kube-proxy / multi-AZ clusters, but this can be addressed
+after the initial implementation.
 
 
 ## Implementation
@@ -182,8 +182,8 @@ region-wide, meaning that a single call will find instances and volumes in all
 zones.  In addition, instance ids and volume ids are unique per-region (and
 hence also per-zone).  I believe they are actually globally unique, but I do
 not know if this is guaranteed; in any case we only need global uniqueness if
-we are to span regions, which will not be supported by Ubernetes-Lite (to do
-that correctly requires an Ubernetes-Full type approach).
+we are to span regions, which will not be supported by multi-AZ clusters (to do
+that correctly requires a full Cluster Federation type approach).
 
 ## GCE Specific Considerations
 
@@ -197,20 +197,20 @@ combine results from calls in all relevant zones.
 A further complexity is that GCE volume names are scoped per-zone, not
 per-region.  Thus it is permitted to have two volumes both named `myvolume` in
 two different GCE zones. (Instance names are currently unique per-region, and
-thus are not a problem for Ubernetes-Lite).
+thus are not a problem for multi-AZ clusters).
 
-The volume scoping leads to a (small) behavioural change for Ubernetes-Lite on
+The volume scoping leads to a (small) behavioural change for multi-AZ clusters on
 GCE.  If you had two volumes both named `myvolume` in two different GCE zones,
 this would not be ambiguous when Kubernetes is operating only in a single zone.
-But, if Ubernetes-Lite is operating in multiple zones, `myvolume` is no longer
+But, when operating a cluster across multiple zones, `myvolume` is no longer
 sufficient to specify a volume uniquely.  Worse, the fact that a volume happens
 to be unambigious at a particular time is no guarantee that it will continue to
 be unambigious in future, because a volume with the same name could
 subsequently be created in a second zone.  While perhaps unlikely in practice,
-we cannot automatically enable Ubernetes-Lite for GCE users if this then causes
+we cannot automatically enable multi-AZ clusters for GCE users if this then causes
 volume mounts to stop working.
 
-This suggests that (at least on GCE), Ubernetes-Lite must be optional (i.e.
+This suggests that (at least on GCE), multi-AZ clusters must be optional (i.e.
 there must be a feature-flag).  It may be that we can make this feature
 semi-automatic in future, by detecting whether nodes are running in multiple
 zones, but it seems likely that kube-up could instead simply set this flag.
@@ -218,14 +218,14 @@ zones, but it seems likely that kube-up could instead simply set this flag.
 For the initial implementation, creating volumes with identical names will
 yield undefined results.  Later, we may add some way to specify the zone for a
 volume (and possibly require that volumes have their zone specified when
-running with Ubernetes-Lite).  We could add a new `zone` field to the
+running in multi-AZ cluster mode).  We could add a new `zone` field to the
 PersistentVolume type for GCE PD volumes, or we could use a DNS-style dotted
 name for the volume name (<name>.<zone>)
 
 Initially therefore, the GCE changes will be to:
 
 1. change kube-up to support creation of a cluster in multiple zones
-1. pass a flag enabling Ubernetes-Lite with kube-up
+1. pass a flag enabling multi-AZ clusters with kube-up
 1. change the kuberentes cloud provider to iterate through relevant zones when resolving items
 1. tag GCE PD volumes with the appropriate zone information
 
diff --git a/federation.md b/federation.md
index fd432c82..3e7055c7 100644
--- a/federation.md
+++ b/federation.md
@@ -34,7 +34,7 @@ Documentation for other releases can be found at
 
 # Kubernetes Cluster Federation
 
-## (a.k.a. "Ubernetes")
+## (previously nicknamed "Ubernetes")
 
 ## Requirements Analysis and Product Proposal
 
@@ -413,7 +413,7 @@ detail to be added here, but feel free to shoot down the basic DNS
 idea in the mean time.  In addition, some applications rely on private
 networking between clusters for security (e.g. AWS VPC or more
 generally VPN).  It should not be necessary to forsake this in
-order to use Ubernetes, for example by being forced to use public
+order to use Cluster Federation, for example by being forced to use public
 connectivity between clusters.
 
 ## Cross-cluster Scheduling
@@ -546,7 +546,7 @@ prefers the Decoupled Hierarchical model for the reasons stated below).
     here, as each underlying Kubernetes cluster can be scaled
     completely independently w.r.t. scheduling, node state management,
     monitoring, network connectivity etc. It is even potentially
-    feasible to stack "Ubernetes" federated clusters (i.e. create
+    feasible to stack federations of clusters (i.e. create
     federations of federations) should scalability of the independent
     Federation Control Plane become an issue (although the author does
     not envision this being a problem worth solving in the short
@@ -595,7 +595,7 @@ prefers the Decoupled Hierarchical model for the reasons stated below).
 
 ![image](federation-high-level-arch.png)
 
-## Ubernetes API
+## Cluster Federation API
 
 It is proposed that this look a lot like the existing Kubernetes API
 but be explicitly multi-cluster.
@@ -603,7 +603,8 @@ but be explicitly multi-cluster.
 + Clusters become first class objects, which can be registered,
    listed, described, deregistered etc via the API.
 + Compute resources can be explicitly requested in specific clusters,
-   or automatically scheduled to the "best" cluster by Ubernetes (by a
+   or automatically scheduled to the "best" cluster by the Cluster
+   Federation control system (by a
    pluggable Policy Engine).
 + There is a federated equivalent of a replication controller type (or
    perhaps a [deployment](deployment.md)),
@@ -627,14 +628,15 @@ Controllers and related Services accordingly).
 This should ideally be delegated to some external auth system, shared
 by the underlying clusters, to avoid duplication and inconsistency.
 Either that, or we end up with multilevel auth.  Local readonly
-eventually consistent auth slaves in each cluster and in Ubernetes
+eventually consistent auth slaves in each cluster and in the Cluster
+Federation control system
 could potentially cache auth, to mitigate an SPOF auth system.
 
 ## Data consistency, failure and availability characteristics
 
-The services comprising the Ubernetes Control Plane) have to run
+The services comprising the Cluster Federation control plane) have to run
    somewhere.  Several options exist here:
-* For high availability Ubernetes deployments, these
+* For high availability Cluster Federation deployments, these
    services may run in either:
   * a dedicated Kubernetes cluster, not co-located in the same
 	 availability zone with any of the federated clusters (for fault
@@ -672,7 +674,7 @@ does the zookeeper config look like for N=3 across 3 AZs -- and how
 does each replica find the other replicas and how do clients find
 their primary zookeeper replica? And now how do I do a shared, highly
 available redis database?  Use a few common specific use cases like
-this to flesh out the detailed API and semantics of Ubernetes.
+this to flesh out the detailed API and semantics of Cluster Federation.
 
 
 <!-- BEGIN MUNGE: GENERATED_ANALYTICS -->
diff --git a/resource-metrics-api.md b/resource-metrics-api.md
index 966d7634..3c45984d 100644
--- a/resource-metrics-api.md
+++ b/resource-metrics-api.md
@@ -79,10 +79,11 @@ The design of the pipeline for collecting application level metrics should
 be revisited and it's not clear whether application level metrics should be
 available in API server so the use case initially won't be supported.
 
-#### Ubernetes
+#### Cluster Federation
 
-Ubernetes might want to consider cluster-level usage (in addition to cluster-level request)
-of running pods when choosing where to schedule new pods. Although Ubernetes is still in design,
+The Cluster Federation control system might want to consider cluster-level usage (in addition to cluster-level request)
+of running pods when choosing where to schedule new pods. Although
+Cluster Federation is still in design,
 we expect the metrics API described here to be sufficient. Cluster-level usage can be
 obtained by summing over usage of all nodes in the cluster.