When kubeadm upgrades a static pod cluster, the old manifests were previously
deleted. This patch alters this behaviour so they are now stored in a
timestamped temporary directory.
Currently kubeadm only performs an upgrade if the etcd cluster is
colocated with the control plane node. As this is only one possible
configuration, kubeadm should support upgrades with etcd clusters
that are not local to the node.
Signed-off-by: Craig Tracey <craigtracey@gmail.com>
- Test HasTLS()
- Instrument throughout upgrade plan and apply
- Update plan_test and apply_test to use new fake Cluster interfaces
- Add descriptions to upgrade range test
- Support KubernetesDir and EtcdDataDir in upgrade tests
- Cover etcdUpgrade in upgrade tests
- Cover upcoming TLSUpgrade in upgrade tests
- Update kubeadm static pod upgrades to use the
kubetypes.ConfigHashAnnotationKey annotation on the mirror pod rather
than generating a hash from the full object info. Previously, a status
update for the pod would allow the upgrade to proceed before the
new static pod manifest was actually deployed.
Signed-off-by: Jason DeTiberus <detiber@gmail.com>
- Place etcd server and peer certs & keys into pki subdir
- Move certs.altName functions to pkiutil + add appendSANstoAltNames()
Share the append logic for the getAltName functions as suggested by
@jamiehannaford.
Move functions/tests to certs/pkiutil as suggested by @luxas.
Update Bazel BUILD deps
- Warn when an APIServerCertSANs or EtcdCertSANs entry is unusable
- Add MasterConfiguration.EtcdPeerCertSANs
- Move EtcdServerCertSANs and EtcdPeerCertSANs under MasterConfiguration.Etcd
- Generate Server and Peer cert for etcd
- Generate Client cert for apiserver
- Add flags / hostMounts for etcd static pod
- Add flags / hostMounts for apiserver static pod
- Generate certs on upgrade of static-pods for etcd/kube-apiserver
- Modify logic for appending etcd flags to staticpod to be safer for external etcd
This is the 2nd attempt. The previous was reverted while we figured out
the regional mirrors (oops).
New plan: k8s.gcr.io is a read-only facade that auto-detects your source
region (us, eu, or asia for now) and pulls from the closest. To publish
an image, push k8s-staging.gcr.io and it will be synced to the regionals
automatically (similar to today). For now the staging is an alias to
gcr.io/google_containers (the legacy URL).
When we move off of google-owned projects (working on it), then we just
do a one-time sync, and change the google-internal config, and nobody
outside should notice.
We can, in parallel, change the auto-sync into a manual sync - send a PR
to "promote" something from staging, and a bot activates it. Nice and
visible, easy to keep track of.
Automatic merge from submit-queue (batch tested with PRs 51682, 51546, 51369, 50924, 51827)
kubeadm: Detect kubelet readiness and error out if the kubelet is unhealthy
**What this PR does / why we need it**:
In order to improve the UX when the kubelet is unhealthy or stopped, or whatever, kubeadm now polls the kubelet's API after 40 and 60 seconds, and then performs an exponential backoff for a total of 155 seconds.
If the kubelet endpoint is not returning `ok` by then, kubeadm gives up and exits.
This will miligate at least 60% of our "[apiclient] Created API client, waiting for control plane to come up" issues in the kubeadm issue tracker 🎉, as kubeadm now informs the user what's wrong and also doesn't deadlock like before.
Demo:
```
lucas@THEGOPHER:~/luxas/kubernetes$ sudo ./kubeadm init --skip-preflight-checks
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[init] Using Kubernetes version: v1.7.4
[init] Using Authorization modes: [Node RBAC]
[preflight] Skipping pre-flight checks
[kubeadm] WARNING: starting in 1.8, tokens expire after 24 hours by default (if you require a non-expiring token use --token-ttl 0)
[certificates] Generated ca certificate and key.
[certificates] Generated apiserver certificate and key.
[certificates] apiserver serving cert is signed for DNS names [thegopher kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.1.115]
[certificates] Generated apiserver-kubelet-client certificate and key.
[certificates] Generated sa key and public key.
[certificates] Generated front-proxy-ca certificate and key.
[certificates] Generated front-proxy-client certificate and key.
[certificates] Valid certificates and keys now exist in "/etc/kubernetes/pki"
[kubeconfig] Wrote KubeConfig file to disk: "admin.conf"
[kubeconfig] Wrote KubeConfig file to disk: "kubelet.conf"
[kubeconfig] Wrote KubeConfig file to disk: "controller-manager.conf"
[kubeconfig] Wrote KubeConfig file to disk: "scheduler.conf"
[controlplane] Wrote Static Pod manifest for component kube-apiserver to "/etc/kubernetes/manifests/kube-apiserver.yaml"
[controlplane] Wrote Static Pod manifest for component kube-controller-manager to "/etc/kubernetes/manifests/kube-controller-manager.yaml"
[controlplane] Wrote Static Pod manifest for component kube-scheduler to "/etc/kubernetes/manifests/kube-scheduler.yaml"
[etcd] Wrote Static Pod manifest for a local etcd instance to "/etc/kubernetes/manifests/etcd.yaml"
[init] Waiting for the kubelet to boot up the control plane as Static Pods from directory "/etc/kubernetes/manifests"
[init] This often takes around a minute; or longer if the control plane images have to be pulled.
[apiclient] All control plane components are healthy after 40.502199 seconds
[markmaster] Will mark node thegopher as master by adding a label and a taint
[markmaster] Master thegopher tainted and labelled with key/value: node-role.kubernetes.io/master=""
[bootstraptoken] Using token: 5776d5.91e7ed14f9e274df
[bootstraptoken] Configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials
[bootstraptoken] Configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token
[bootstraptoken] Creating the "cluster-info" ConfigMap in the "kube-public" namespace
[uploadconfig] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace
[addons] Applied essential addon: kube-dns
[addons] Applied essential addon: kube-proxy
Your Kubernetes master has initialized successfully!
To start using your cluster, you need to run (as a regular user):
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config
You should now deploy a pod network to the cluster.
Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at:
http://kubernetes.io/docs/admin/addons/
You can now join any number of machines by running the following on each node
as root:
kubeadm join --token 5776d5.91e7ed14f9e274df 192.168.1.115:6443 --discovery-token-ca-cert-hash sha256:6f301ce8c3f5f6558090b2c3599d26d6fc94ffa3c3565ffac952f4f0c7a9b2a9
lucas@THEGOPHER:~/luxas/kubernetes$ sudo ./kubeadm reset
[preflight] Running pre-flight checks
[reset] Stopping the kubelet service
[reset] Unmounting mounted directories in "/var/lib/kubelet"
[reset] Removing kubernetes-managed containers
[reset] Deleting contents of stateful directories: [/var/lib/kubelet /etc/cni/net.d /var/lib/dockershim /var/run/kubernetes /var/lib/etcd]
[reset] Deleting contents of config directories: [/etc/kubernetes/manifests /etc/kubernetes/pki]
[reset] Deleting files: [/etc/kubernetes/admin.conf /etc/kubernetes/kubelet.conf /etc/kubernetes/controller-manager.conf /etc/kubernetes/scheduler.conf]
lucas@THEGOPHER:~/luxas/kubernetes$ sudo systemctl stop kubelet
lucas@THEGOPHER:~/luxas/kubernetes$ sudo ./kubeadm init --skip-preflight-checks
[kubeadm] WARNING: kubeadm is in beta, please do not use it for production clusters.
[init] Using Kubernetes version: v1.7.4
[init] Using Authorization modes: [Node RBAC]
[preflight] Skipping pre-flight checks
[kubeadm] WARNING: starting in 1.8, tokens expire after 24 hours by default (if you require a non-expiring token use --token-ttl 0)
[certificates] Generated ca certificate and key.
[certificates] Generated apiserver certificate and key.
[certificates] apiserver serving cert is signed for DNS names [thegopher kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.1.115]
[certificates] Generated apiserver-kubelet-client certificate and key.
[certificates] Generated sa key and public key.
[certificates] Generated front-proxy-ca certificate and key.
[certificates] Generated front-proxy-client certificate and key.
[certificates] Valid certificates and keys now exist in "/etc/kubernetes/pki"
[kubeconfig] Wrote KubeConfig file to disk: "admin.conf"
[kubeconfig] Wrote KubeConfig file to disk: "kubelet.conf"
[kubeconfig] Wrote KubeConfig file to disk: "controller-manager.conf"
[kubeconfig] Wrote KubeConfig file to disk: "scheduler.conf"
[controlplane] Wrote Static Pod manifest for component kube-apiserver to "/etc/kubernetes/manifests/kube-apiserver.yaml"
[controlplane] Wrote Static Pod manifest for component kube-controller-manager to "/etc/kubernetes/manifests/kube-controller-manager.yaml"
[controlplane] Wrote Static Pod manifest for component kube-scheduler to "/etc/kubernetes/manifests/kube-scheduler.yaml"
[etcd] Wrote Static Pod manifest for a local etcd instance to "/etc/kubernetes/manifests/etcd.yaml"
[init] Waiting for the kubelet to boot up the control plane as Static Pods from directory "/etc/kubernetes/manifests"
[init] This often takes around a minute; or longer if the control plane images have to be pulled.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz' failed with error: Get http://localhost:10255/healthz: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz' failed with error: Get http://localhost:10255/healthz: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz' failed with error: Get http://localhost:10255/healthz: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz/syncloop' failed with error: Get http://localhost:10255/healthz/syncloop: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz/syncloop' failed with error: Get http://localhost:10255/healthz/syncloop: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz/syncloop' failed with error: Get http://localhost:10255/healthz/syncloop: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz' failed with error: Get http://localhost:10255/healthz: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz/syncloop' failed with error: Get http://localhost:10255/healthz/syncloop: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10255/healthz' failed with error: Get http://localhost:10255/healthz: dial tcp 127.0.0.1:10255: getsockopt: connection refused.
Unfortunately, an error has occurred:
timed out waiting for the condition
This error is likely caused by that:
- The kubelet is not running
- The kubelet is unhealthy due to a misconfiguration of the node in some way (required cgroups disabled)
- There is no internet connection; so the kubelet can't pull the following control plane images:
- gcr.io/google_containers/kube-apiserver-amd64:v1.7.4
- gcr.io/google_containers/kube-controller-manager-amd64:v1.7.4
- gcr.io/google_containers/kube-scheduler-amd64:v1.7.4
You can troubleshoot this for example with the following commands if you're on a systemd-powered system:
- 'systemctl status kubelet'
- 'journalctl -xeu kubelet'
couldn't initialize a Kubernetes cluster
```
In this demo, I'm first starting kubeadm normally and everything works as usual.
In the second case, I'm explicitely stopping the kubelet so it doesn't run, and skipping preflight checks, so that kubeadm doesn't even try to exec `systemctl start kubelet` like it does usually.
That obviously results in a non-working system, but now kubeadm tells the user what's the problem instead of waiting forever.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #
Fixes: https://github.com/kubernetes/kubeadm/issues/377
**Special notes for your reviewer**:
**Release note**:
```release-note
kubeadm: Detect kubelet readiness and error out if the kubelet is unhealthy
```
@kubernetes/sig-cluster-lifecycle-pr-reviews @pipejakob
cc @justinsb @kris-nova @lukemarsden as well as you wanted this feature :)
