This PR contains Kubelet changes to enable attach/detach controller control.
* It introduces a new "enable-controller-attach-detach" kubelet flag to
enable control by controller. Default enabled.
* It removes all references "SafeToDetach" annoation from controller.
* It adds the new VolumesInUse field to the Node Status API object.
* It modifies the controller to use VolumesInUse instead of SafeToDetach
annotation to gate detachment.
* There is a bug in node-problem-detector that causes VolumesInUse to
get reset every 30 seconds. Issue https://github.com/kubernetes/node-problem-detector/issues/9
opened to fix that.
This allows kube-controller-manager to allocate CIDRs to nodes (with
allocate-node-cidrs=true), but will not try to configure them on the
cloud provider, even if the cloud provider supports Routes.
The default is configure-cloud-routes=true, and it will only try to
configure routes if allocate-node-cidrs is also configured, so the
default behaviour is unchanged.
This is useful because on AWS the cloud provider configures routes by
setting up VPC routing table entries, but there is a limit of 50
entries. So setting configure-cloud-routes on AWS would allow us to
continue to allocate node CIDRs as today, but replace the VPC
route-table mechanism with something not limited to 50 nodes.
We can't just turn off the cloud-provider entirely because it also
controls other things - node discovery, load balancer creation etc.
Fix#25602
Split controller cache into actual and desired state of world.
Controller will only operate on volumes scheduled to nodes that
have the "volumes.kubernetes.io/controller-managed-attach" annotation.
Automatic merge from submit-queue
Use protobufs by default to communicate with apiserver (still store JSONs in etcd)
@lavalamp @kubernetes/sig-api-machinery
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Cache Webhook Authentication responses
Add a simple LRU cache w/ 2 minute TTL to the webhook authenticator.
Kubectl is a little spammy, w/ >= 4 API requests per command. This also prevents a single unauthenticated user from being able to DOS the remote authenticator.
This patch adds the --exit-on-lock-contention flag, which must be used
in conjunction with the --lock-file flag. When provided, it causes the
kubelet to wait for inotify events for that lock file. When an 'open'
event is received, the kubelet will exit.
Automatic merge from submit-queue
WIP v0 NVIDIA GPU support
```release-note
* Alpha support for scheduling pods on machines with NVIDIA GPUs whose kubelets use the `--experimental-nvidia-gpus` flag, using the alpha.kubernetes.io/nvidia-gpu resource
```
Implements part of #24071 for #23587
I am not familiar with the scheduler enough to know what to do with the scores. Mostly punting for now.
Missing items from the implementation plan: limitranger, rkt support, kubectl
support and docs
cc @erictune @davidopp @dchen1107 @vishh @Hui-Zhi @gopinatht
Automatic merge from submit-queue
Webhook Token Authenticator
Add a webhook token authenticator plugin to allow a remote service to make authentication decisions.
Implements part of #24071
I am not familiar with the scheduler enough to know what to do with the scores. Punting for now.
Missing items from the implementation plan: limitranger, rkt support, kubectl
support and user docs
Automatic merge from submit-queue
Reimplement 'pause' in C - smaller footprint all around
Statically links against musl. Size of amd64 binary is 3560 bytes.
I couldn't test the arm binary since I have no hardware to test it on, though I assume we want it to work on a raspberry pi.
This PR also adds the gcc5/musl cross compiling image used to build the binaries.
@thockin
The codec factory should support two distinct interfaces - negotiating
for a serializer with a client, vs reading or writing data to a storage
form (etcd, disk, etc). Make the EncodeForVersion and DecodeToVersion
methods only take Encoder and Decoder, and slight refactoring elsewhere.
In the storage factory, use a content type to control what serializer to
pick, and use the universal deserializer. This ensures that storage can
read JSON (which might be from older objects) while only writing
protobuf. Add exceptions for those resources that may not be able to
write to protobuf (specifically third party resources, but potentially
others in the future).
Automatic merge from submit-queue
Make etcd cache size configurable
Instead of the prior 50K limit, allow users to specify a more sensible size for their cluster.
I'm not sure what a sensible default is here. I'm still experimenting on my own clusters. 50 gives me a 270MB max footprint. 50K caused my apiserver to run out of memory as it exceeded >2GB. I believe that number is far too large for most people's use cases.
There are some other fundamental issues that I'm not addressing here:
- Old etcd items are cached and potentially never removed (it stores using modifiedIndex, and doesn't remove the old object when it gets updated)
- Cache isn't LRU, so there's no guarantee the cache remains hot. This makes its performance difficult to predict. More of an issue with a smaller cache size.
- 1.2 etcd entries seem to have a larger memory footprint (I never had an issue in 1.1, even though this cache existed there). I suspect that's due to image lists on the node status.
This is provided as a fix for #23323
bridge-nf-call-iptables appears to only be relevant when the containers are
attached to a Linux bridge, which is usually the case with default Kubernetes
setups, docker, and flannel. That ensures that the container traffic is
actually subject to the iptables rules since it traverses a Linux bridge
and bridged traffic is only subject to iptables when bridge-nf-call-iptables=1.
But with other networking solutions (like openshift-sdn) that don't use Linux
bridges, bridge-nf-call-iptables may not be not relevant, because iptables is
invoked at other points not involving a Linux bridge.
The decision to set bridge-nf-call-iptables should be influenced by networking
plugins, so push the responsiblity out to them. If no network plugin is
specified, fall back to the existing bridge-nf-call-iptables=1 behavior.
