* Upgrade kubernetes to v1.13.0
* Remove all precense of scheduler.alpha.kubernetes.io/critical-pod in templates
* Fix cert dir
* Use kubespray v2.8 as baseline for gitlab
* Remove non-kubeadm deployment
* More cleanup
* More cleanup
* More cleanup
* More cleanup
* Fix gitlab
* Try stop gce first before absent to make the delete process work
* More cleanup
* Fix bug with checking if kubeadm has already run
* Fix bug with checking if kubeadm has already run
* More fixes
* Fix test
* fix
* Fix gitlab checkout untill kubespray 2.8 is on quay
* Fixed
* Add upgrade path from non-kubeadm to kubeadm. Revert ssl path
* Readd secret checking
* Do gitlab checks from v2.7.0 test upgrade path to 2.8.0
* fix typo
* Fix CI jobs to kubeadm again. Fix broken hyperkube path
* Fix gitlab
* Fix rotate tokens
* More fixes
* More fixes
* Fix tokens
* Set configure-cloud-routes=false as default if no network plugin is used
As configure-cloud-routes default value is `true`, so it need to be set to `false` when not required to avoid error messages like:
"Couldn't reconcile node routes: error listing routes: unable to find route table for AWS cluster"
on, for example, AWS installations that don't use cloud native routing.
* Update kube-controller-manager.manifest.j2
remove extra spaces
Introduced variable node_taints which can be set in inventory for
specific hosts or in group_vars, which generates --register-with-taints
command line argument for kubelet.
* Update defaults to match k8s 1.12 suggestions
* Test if Netchecker works with node ip instead of localhost
* Update defaults to ipvs and coredns
* Update defaults for kube_apiserver_insecure_port
* Update main.yaml
Now the `kubespray-aws-inventory.py` script always set a node_labels key
to ansible_host.
When AWS instance did not set property labels, it would be an empty
string.
The TASK `Write kubelet config file (kubeadm or non-kubeadm)` will
failed with a msg:
`AnsibleUndefinedVariable: 'unicode object' has no attribute 'items'`.
When using resolvconf_mode host_resolvconf, there is an early DNS
config stage where Kubernetes cluster DNS is not injected for host
DNS intially. Later, the cluster DNS is enabled, but we do not
need to run every task from the kubernetes/preinstall role.
* warning on meta flush_handlers
* avoid rm
* avoid "Module remote_tmp /root/.ansible/tmp did not exist and was created with a mode of 0700, this may cause issues when running as another user. To avoid this, create the remote_tmp dir with the correct permissions manually" warning on subsequent tasks using blockinfile
* is match
* failed
* version_compare
* succeeded
* skipped
* success
* version_compare becomes version since ansible 2.5
* ansible minimal version updated in doc and spec
* last version_compare
* [jjo] add kube-router support
Fixescloudnativelabs/kube-router#147.
* add kube-router as another network_plugin choice
* support most used kube-router flags via
`kube_router_foo` vars as other plugins
* implement replacing kube-proxy (--run-service-proxy=true) via
`kube_proxy_mode: none`, verified in a _non kubeadm_enabled_
install, should also work for recent kubeadm releases via
`skipKubeProxyInstall: true` config
* [jjo] address PR#3339 review from @woopstar
* add busybox image used by kube-router to downloads
* fix busybox download groups key
* rework kubeadm_enabled + kube_router_run_service_proxy
- verify it working ok w/the kubeadm_enabled and
kube_router_run_service_proxy true or false
- introduce `kube_proxy_remove` fact, to decouple logic
from kube_proxy_mode (which affects kubeadm configmap
settings, thus no-good to ab-use it to 'none')
* improve kube-router.md re: kubeadm_enabled and kube_router_run_service_proxy
* address @woopstar latest review
* add inventory/sample/group_vars/k8s-cluster/k8s-net-kube-router.yml
* fix kube_router_run_service_proxy conditional for kube-proxy removal
* fix kube_proxy_remove fact (w/ |bool), add some needed kube-proxy tags on my and existing changes
* update kube-router tolerations for 1.12 compatibility
* add PriorityClass to kube-router DaemonSet
The hosts(5) manpage clearly states that the first entry is the
"canonical name", or FQDN (Fully-Qualified Domain Name):
IP_address canonical_hostname [aliases...]
By using the alias as a first entry, `hostname -f` does not return the
correct domain which breaks all sorts of unrelated functionality (it
has impact over email server configuration, for example).
* [jjo] add DIND support to contrib/
- add contrib/dind with ansible playbook to
create "node" containers, and setup them to mimic
host nodes as much as possible (using Ubuntu images),
see contrib/dind/README.md
- nodes' /etc/hosts editing via `blockinfile` and
`lineinfile` need `unsafe_writes: yes` because /etc/hosts
are mounted by docker, and thus can't be handled atomically
(modify copy + rename)
* dind-host role: set node container hostname on creation
* add "Resulting deployment" section with some CLI outputs
* typo
* selectable node_distro: debian, ubuntu
* some fixes for node_distro: ubuntu
* cpu optimization: add early `pkill -STOP agetty`
* typo
* add centos dind support ;)
* add kubespray-dind.yaml, support fedora
- add kubespray-dind.yaml (former custom.yaml at README.md)
- rework README.md as per above
- use some YAML power to share distros' commonality
- add fedora support
* create unique /etc/machine-id and other updates
- create unique /etc/machine-id in each docker node,
used as seed for e.g. weave mac addresses
- with above, now netchecker 100% passes WoHooOO!
🎉🎉🎉
- updated README.md output from (1.12.1, verified
netcheck)
* minor typos
* fix centos node creation, needs earlier udevadm removal to avoid flaky facts, also verified netcheck Ok \o/
* add Q&D test-distros.sh, back to manual /etc/machine-id hack
* run-test-distros.sh cosmetics and minor fixes
* run-test-distros.sh: $rc fix and minor formatting changes
* run-test-distros.sh output cosmetics
- Local Volume StorageClass configuration is now manged by `local_volume_provisioner_storage_classes`, a list of maps that specifies local storage classes with `name` `host_dir` and `mount_dir` keys per entry
- Tasks and templates updated to loop through local volume storage classes
- Previous defaults for path/class names were not changed
- Fixed an issue where a `kubernetes/preinstall` was creating directories inconsistently with the `kubernetes-apps/external_provisioner/local_volume_provisioner` task
* Fix the jinja expression for openstack_tenant_id
OS_PROJECT_ID is obsolete in keystone v3 and jinja expression
doesn't set openstack_tenant_id as expected because of
undefined env var. Fixed the expression.
* Fix the dic iteration method in the kubelet template
Kubelet template rendering errors when additional Node lables are
added and using Python3. Update the method to be compatible to both
python2/3
Node lables doesn't work
* Changes to assign pod priority to kube components.
* Removed the boolean flag pod_priority_assignment
* Created new priorityclass k8s-cluster-critical
* Created new priorityclass k8s-cluster-critical
* Fixed the trailing spaces
* Fixed the trailing spaces
* Added kube version check while creating Priority Class k8s-cluster-critical
* Moved k8s-cluster-critical.yml
* Moved k8s-cluster-critical.yml to kube_config_dir
OS_PROJECT_ID is obsolete in keystone v3 and jinja expression
doesn't set openstack_tenant_id as expected because of
undefined env var. Fixed the expression.
ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version
remove empty when line
ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version
force kubeadm upgrade due to failure without --force flag
ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version
added nodeSelector to have compatibility with hybrid cluster with win nodes, also fix for download with missing container type
fixes in syntax and LF for newline in files
fix on yamllint check
ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version
some cleanup for innecesary lines
remove conditions for nodeselector
* calico upgrade to v3
* update calico_rr version
* add missing file
* change contents of main.yml as it was left old version
* enable network policy by default
* remove unneeded task
* Fix kubelet calico settings
* fix when statement
* switch back to node-kubeconfig.yaml
Upgrade Kubernetes to V1.11.2
The kubeadm configuration file version has been upgraded from v1alpha1 to v1alpha2
Add bootstrap kubeadm-config.yaml with external etcd
ingress-nginx 0.16.2 (https://github.com/kubernetes/ingress-nginx/releases/tag/nginx-0.16.2)
This patch simplify ingress-nginx deployment by default deploy on
master, with customizable options; on the other hand, remove the
additional Ansible group "kube-ingress" and its k8s node label
injection.
Reference to https://kubernetes.io/docs/concepts/services-networking/ingress/#prerequisites:
GCE/Google Kubernetes Engine deploys an ingress controller on the master.
By changing `ingress_nginx_nodeselector` plus custom k8s node
label, user could customize the DaemonSet deployment target.
If `ingress_nginx_nodeselector` is empty, will deploy DaemonSet on
every k8s node.
Red Hat has this theory that binaries in sbin are too dangerous to be on
the default path, but we need them anyway.
RH7 has /sbin and /usr/sbin as symlinks, so that is no longer important.
I'm adding it to the `PATH` instead of making the path to `modinfo`
absolute because I am worried about breaking support for other
distributions.
On Aarch64, the default cgroup driver for docker is systemd
instead of cgroupfs. Should conform kubelet to use systemd
as cgroup driver as well to keep it consistent with docker.
Without this change, below exception will be raised.
/usr/bin/docker-current: Error response from daemon: shim
error: docker-runc not installed on system.
Change-Id: Id496ec9eaac6580e4da2f3ef1a386c9abc2a5129
The number of pods on a given node is determined by the --max-pods=k
directive. When the address space is exhausted, no more pods can be
scheduled even if from the --max-pods-perspective, the node still has
capacity.
The special case that a pod is scheduled and uses the node IP in the
host network namespace is too "soft" to derive a guarantee.
Comparing kubelet_max_pods with kube_network_node_prefix when given
allows to assert that pod limits match the CIDR address space.
* Move front-proxy-client certs back to kube mount
We want the same CA for all k8s certs
* Refactor vault to use a third party module
The module adds idempotency and reduces some of the repetitive
logic in the vault role
Requires ansible-modules-hashivault on ansible node and hvac
on the vault hosts themselves
Add upgrade test scenario
Remove bootstrap-os tags from tasks
* fix upgrade issues
* improve unseal logic
* specify ca and fix etcd check
* Fix initialization check
bump machine size
* sysctl file should be in defaults so that it can be overriden
* Change sysctl_file_path to be consistent with roles/kubernetes/preinstall/defaults/main.yml
The openssl package on Tumbleweed is actually a virtual package covering
openssl-1.0.0 and openssl-1.1.0 implementations. It defaults to 1.1.0 so
when trying to install it and openssl-1.0.0 is installed, zypper fails
with conflicts. As such, lets explicitly pull the package that we need
which also updates the virtual one.
Co-authored-by: Markos Chandras <mchandras@suse.de>
While `do` looks cleaner, forcing this extra option in ansible.cfg
seems to be more invasive. It would be better to keep the traditional
approach of `set dummy = ` instead.
The current way to setup the etc cluster is messy and buggy.
- It checks for cluster is healthy before the cluster is even created.
- The unit files are started on handlers, not in the task, so you mess with "flush handlers".
- The join_member.yml is not used.
- etcd events cluster is not configured for kubeadm
- remove duplicate runs between running the role on etcd nodes and k8s nodes
Added CoreDNS to downloads
Updated with labels. Should now work without RBAC too
Fix DNS settings on hosts
Rename CoreDNS service from kube-dns to coredns
Add rotate based on http://edgeofsanity.net/rant/2017/12/20/systemd-resolved-is-broken.html
Updated docs with CoreDNS info
Added labels and fixed minor settings from official yaml file: https://github.com/kubernetes/kubernetes/blob/release-1.9/cluster/addons/dns/coredns.yaml.sed
Added a secondary deployment and secondary service ip. This is to mitigate dns timeouts and create high resitency for failures. See discussion at 'https://github.com/coreos/coreos-kubernetes/issues/641#issuecomment-281174806'
Set dns list correct. Thanks to @whereismyjetpack
Only download KubeDNS or CoreDNS if selected
Move dns cleanup to its own file and import tasks based on dns mode
Fix install of KubeDNS when dnsmask_kubedns mode is selected
Add new dns option coredns_dual for dual stack deployment. Added variable to configure replicas deployed. Updated docs for dual stack deployment. Removed rotate option in resolv.conf.
Run DNS manifests for CoreDNS and KubeDNS
Set skydns servers on dual stack deployment
Use only one template for CoreDNS dual deployment
Set correct cluster ip for the dns server
* Added option for encrypting secrets to etcd
* Fix keylength to 32
* Forgot the default
* Rename secrets.yaml to secrets_encryption.yaml
* Fix static path for secrets file to use ansible variable
* Rename secrets.yaml.j2 to secrets_encryption.yaml.j2
* Base64 encode the token
* Fixed merge error
* Changed path to credentials dir
* Update path to secrets file which is now readable inside the apiserver container. Set better file permissions
* Add encryption option to k8s-cluster.yml
Setting the following:
```
kube_kubeadm_controller_extra_args:
address: 0.0.0.0
terminated-pod-gc-threshold: "100"
```
Results in `terminated-pod-gc-threshold: 100` in the kubeadm config file. But it has to be a string to work.
to the API server configuration.
This solves the problem where if you have non-resolvable node names,
and try to scale the server by adding new nodes, kubectl commands
start to fail for newly added nodes, giving a TCP timeout error when
trying to resolve the node hostname against a public DNS.
* Fix run kubectl error
Fix run kubectl error when first master doesn't work
* if access_ip is define use first_kube_master
else different master use a different ip
* Delete set first_kube_master and use kube_apiserver_access_address
* Set filemode to 0640
weave-net.yml file is readable by all users on the host. It however contains the weave_password to encrypt all pod communication. It should only be readable by root.
* Set mode 0640 on users_file with basic auth
* Added cilium support
* Fix typo in debian test config
* Remove empty lines
* Changed cilium version from <latest> to <v1.0.0-rc3>
* Add missing changes for cilium
* Add cilium to CI pipeline
* Fix wrong file name
* Check kernel version for cilium
* fixed ci error
* fixed cilium-ds.j2 template
* added waiting for cilium pods to run
* Fixed missing EOF
* Fixed trailing spaces
* Fixed trailing spaces
* Fixed trailing spaces
* Fixed too many blank lines
* Updated tolerations,annotations in cilium DS template
* Set cilium_version to iptables-1.9 to see if bug is fixed in CI
* Update cilium image tag to v1.0.0-rc4
* Update Cilium test case CI vars filenames
* Add optional prometheus flag, adjust initial readiness delay
* Update README.md with cilium info
Even though there it kubeadm_token_ttl=0 which means that kubeadm token never expires, it is not present in `kubeadm token list` after cluster is provisioned (at least after it is running for some time) and there is issue regarding this https://github.com/kubernetes/kubeadm/issues/335, so we need to create a new temporary token during the cluster upgrade.
Ansible automatically installs the python-apt package when using
the 'apt' Ansible module, if python-apt is not present. This patch
removes the (unneeded) explicit installation in the Kubespray
'preinstall' role.
* allow installs to not have hostname overriden with fqdn from inventory
* calico-config no longer requires local as and will default to global
* when cloudprovider is not defined, use the inventory_hostname for cni-calico
* allow reset to not restart network (buggy nodes die with this cmd)
* default kube_override_hostname to inventory_hostname instead of ansible_hostname
Cloud resolvers are mandatory for hosts on GCE and OpenStack
clouds. The 8.8.8.8 alternative resolver was dropped because
there is already a default nameserver. The new var name
reflects the purpose better.
Also restart apiserver when modifying dns settings.
If you configure your external loadbalancer to do a simple tcp pass-through to the api servers, and you do not use a DNS FQDN but just the ip, then you need to add the ip adress to the certificates too.
Example config:
```
## External LB example config
apiserver_loadbalancer_domain_name: "10.50.63.10"
loadbalancer_apiserver:
address: 10.50.63.10
port: 8383
```
kube-proxy is complaining of missing modules at startup. There is a plan
to also support an LVS implementation of kube-proxy in additon to
userspace and iptables
Update checksum for kubeadm
Use v1.9.0 kubeadm params
Include hash of ca.crt for kubeadm join
Update tag for testing upgrades
Add workaround for testing upgrades
Remove scale CI scenarios because of slow inventory parsing
in ansible 2.4.x.
Change region for tests to us-central1 to
improve ansible performance
Starting with Kubernetes v1.8.4, kubelet ignores the AWS cloud
provider string and uses the override hostname, which fails
Node admission checks.
Fixes#2094
As we have seen with other containers, sometimes container removal fails on the first attempt due to some Docker bugs. Retrying typically corrects the issue.
This allows `kube_apiserver_insecure_port` to be set to 0 (disabled).
Rework of #1937 with kubeadm support
Also, fixed an issue in `kubeadm-migrate-certs` where the old apiserver cert was copied as the kubeadm key
* Allow setting --bind-address for apiserver hyperkube
This is required if you wish to configure a loadbalancer (e.g haproxy)
running on the master nodes without choosing a different port for the
vip from that used by the API - in this case you need the API to bind to
a specific interface, then haproxy can bind the same port on the VIP:
root@overcloud-controller-0 ~]# netstat -taupen | grep 6443
tcp 0 0 192.168.24.6:6443 0.0.0.0:* LISTEN 0 680613 134504/haproxy
tcp 0 0 192.168.24.16:6443 0.0.0.0:* LISTEN 0 653329 131423/hyperkube
tcp 0 0 192.168.24.16:6443 192.168.24.16:58404 ESTABLISHED 0 652991 131423/hyperkube
tcp 0 0 192.168.24.16:58404 192.168.24.16:6443 ESTABLISHED 0 652986 131423/hyperkube
This can be achieved e.g via:
kube_apiserver_bind_address: 192.168.24.16
* Address code review feedback
* Update kube-apiserver.manifest.j2
* Add Contiv support
Contiv is a network plugin for Kubernetes and Docker. It supports
vlan/vxlan/BGP/Cisco ACI technologies. It support firewall policies,
multiple networks and bridging pods onto physical networks.
* Update contiv version to 1.1.4
Update contiv version to 1.1.4 and added SVC_SUBNET in contiv-config.
* Load openvswitch module to workaround on CentOS7.4
* Set contiv cni version to 0.1.0
Correct contiv CNI version to 0.1.0.
* Use kube_apiserver_endpoint for K8S_API_SERVER
Use kube_apiserver_endpoint as K8S_API_SERVER to make contiv talks
to a available endpoint no matter if there's a loadbalancer or not.
* Make contiv use its own etcd
Before this commit, contiv is using a etcd proxy mode to k8s etcd,
this work fine when the etcd hosts are co-located with contiv etcd
proxy, however the k8s peering certs are only in etcd group, as a
result the etcd-proxy is not able to peering with the k8s etcd on
etcd group, plus the netplugin is always trying to find the etcd
endpoint on localhost, this will cause problem for all netplugins
not runnign on etcd group nodes.
This commit make contiv uses its own etcd, separate from k8s one.
on kube-master nodes (where net-master runs), it will run as leader
mode and on all rest nodes it will run as proxy mode.
* Use cp instead of rsync to copy cni binaries
Since rsync has been removed from hyperkube, this commit changes it
to use cp instead.
* Make contiv-etcd able to run on master nodes
* Add rbac_enabled flag for contiv pods
* Add contiv into CNI network plugin lists
* migrate contiv test to tests/files
Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com>
* Add required rules for contiv netplugin
* Better handling json return of fwdMode
* Make contiv etcd port configurable
* Use default var instead of templating
* roles/download/defaults/main.yml: use contiv 1.1.7
Signed-off-by: Cristian Staretu <cristian.staretu@gmail.com>
* Defaults for apiserver_loadbalancer_domain_name
When loadbalancer_apiserver is defined, use the
apiserver_loadbalancer_domain_name with a given default value.
Fix unconsistencies for checking if apiserver_loadbalancer_domain_name
is defined AND using it with a default value provided at once.
Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
* Define defaults for LB modes in common defaults
Adjust the defaults for apiserver_loadbalancer_domain_name and
loadbalancer_apiserver_localhost to come from a single source, which is
kubespray-defaults. Removes some confusion and simplefies the code.
Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
Thought this wasn't required at first but I forgot there's no auto flush at the end of these tasks since the `kubernetes/master` role is not the end of the play.
* Fixes an issue where apiserver and friends (controller manager, scheduler) were prevented from restarting after manifests/secrets are changed. This occurred when a replaced kubelet doesn't reconcile new master manifests, which caused old master component versions to linger during deployment. In my case this was causing upgrades from k8s 1.6/1.7 -> k8s 1.8 to fail
* Improves transitions from kubelet container to host kubelet by preventing issues where kubelet container reappeared during the deployment
This allows `kube_apiserver_insecure_port` to be set to 0 (disabled). It's working, but so far I have had to:
1. Make the `uri` module "Wait for apiserver up" checks use `kube_apiserver_port` (HTTPS)
2. Add apiserver client cert/key to the "Wait for apiserver up" checks
3. Update apiserver liveness probe to use HTTPS ports
4. Set `kube_api_anonymous_auth` to true to allow liveness probe to hit apiserver's /healthz over HTTPS (livenessProbes can't use client cert/key unfortunately)
5. RBAC has to be enabled. Anonymous requests are in the `system:unauthenticated` group which is granted access to /healthz by one of RBAC's default ClusterRoleBindings. An equivalent ABAC rule could allow this as well.
Changes 1 and 2 should work for everyone, but 3, 4, and 5 require new coupling of currently independent configuration settings. So I also added a new settings check.
Options:
1. The problem goes away if you have both anonymous-auth and RBAC enabled. This is how kubeadm does it. This may be the best way to go since RBAC is already on by default but anonymous auth is not.
2. Include conditional templates to set a different liveness probe for possible combinations of `kube_apiserver_insecure_port = 0`, RBAC, and `kube_api_anonymous_auth` (won't be possible to cover every case without a guaranteed authorizer for the secure port)
3. Use basic auth headers for the liveness probe (I really don't like this, it adds a new dependency on basic auth which I'd also like to leave independently configurable, and it requires encoded passwords in the apiserver manifest)
Option 1 seems like the clear winner to me, but is there a reason we wouldn't want anonymous-auth on by default? The apiserver binary defaults anonymous-auth to true, but kubespray's default was false.
* Change deprecated vagrant ansible flag 'sudo' to 'become'
* Workaround ansible bug where access var via dict doesn't get real value
When accessing a variable via it's name "{{ foo }}" its value is
retrieved. But when the variable value is retrieved via the vars-dict
"{{ vars['foo'] }}" this doesn't resolve the expression of the variable
any more due to a bug. So e.g. a expression foo="{{ 1 == 1 }}" isn't
longer resolved but just returned as string "1 == 1".
* Make file yamllint complient
Some time ago I think the hardcoded `/var/lib/docker` was required, but kubelet running in a container has been aware of the Docker path since at least as far back as k8s 1.6.
Without this change, you see a large number of errors in the kubelet logs if you installed with a non-default `docker_daemon_graph`
* Refactor downloads to use download role directly
Also disable fact delegation so download delegate works acros OSes.
* clean up bools and ansible_os_family conditionals
* Update main.yml
Needs to set up resolv.conf before updating Yum cache otherwise no name resolution available (resolv.conf empty).
* Update main.yml
Removing trailing spaces
* Add possibility to insert more ip adresses in certificates
* Add newline at end of files
* Move supp ip parameters to k8s-cluster group file
* Add supplementary addresses in kubeadm master role
* Improve openssl indexes
* don't try to install this rpm on fedora atomic
* add docker 1.13.1 for fedora
* built-in docker unit file is sufficient, as tested on both fedora and centos atomic
* Change file used to check kubeadm upgrade method
Test for ca.crt instead of admin.conf because admin.conf
is created during normal deployment.
* more fixes for upgrade
* Rename dns_server to dnsmasq_dns_server so that it includes role prefix
as the var name is generic and conflicts when integrating with existing ansible automation.
* Enable selinux state to be configurable with new var preinstall_selinux_state
PID namespace sharing is disabled only in Kubernetes 1.7.
Explicitily enabling it by default could help reduce unexpected
results when upgrading to or downgrading from 1.7.
This follows pull request #1677, adding the cgroup-driver
autodetection also for kubeadm way of deploying.
Info about this and the possibility to override is added to the docs.
Red Hat family platforms run docker daemon with `--exec-opt
native.cgroupdriver=systemd`. When kubespray tried to start kubelet
service, it failed with:
Error: failed to run Kubelet: failed to create kubelet: misconfiguration: kubelet cgroup driver: "cgroupfs" is different from docker cgroup driver: "systemd"
Setting kubelet's cgroup driver to the correct value for the platform
fixes this issue. The code utilizes autodetection of docker's cgroup
driver, as different RPMs for the same distro may vary in that regard.
