4fe2e82d88
Updates the dnsmasq cache/mux layer to be managed by dnsmasq-nanny.
dnsmasq-nanny manages dnsmasq based on values from the
kube-system:kube-dns configmap:
"stubDomains": {
"acme.local": ["1.2.3.4"]
},
is a map of domain to list of nameservers for the domain. This is used
to inject private DNS domains into the kube-dns namespace. In the above
example, any DNS requests for *.acme.local will be served by the
nameserver 1.2.3.4.
"upstreamNameservers": ["8.8.8.8", "8.8.4.4"]
is a list of upstreamNameservers to use, overriding the configuration
specified in /etc/resolv.conf.
Cluster add-ons
Overview
Cluster add-ons are resources like Services and Deployments (with pods) that are shipped with the Kubernetes binaries and are considered an inherent part of the Kubernetes clusters.
There are currently two classes of add-ons:
- Add-ons that will be reconciled.
- Add-ons that will be created if they don't exist.
More details could be found in addon-manager/README.md.
Cooperating Horizontal / Vertical Auto-Scaling with "reconcile class addons"
"Reconcile" class addons will be periodically reconciled to the original state given
by the initial config. In order to make Horizontal / Vertical Auto-scaling functional,
the related fields in config should be left unset. More specifically, leave replicas
in ReplicationController / Deployment / ReplicaSet unset for Horizontal Scaling,
leave resources for container unset for Vertical Scaling. The periodic reconcile
won't clobbered these fields, hence they could be managed by Horizontal / Vertical
Auto-scaler.
Add-on naming
The suggested naming for most of the resources is <basename> (with no version number).
Though resources like Pod, ReplicationController and DaemonSet are exceptional.
It would be hard to update Pod because many fields in Pod are immutable. For
ReplicationController and DaemonSet, in-place update may not trigger the underlying
pods to be re-created. You probably need to change their names during update to trigger
a complete deletion and creation.