According to code apiserver, scheduler, controller-manager, proxy don't
use resolution of objects they created. It's not harmful to change
policy to have external resolver.
Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>
In kubernetes 1.6 ClusterFirstWithHostNet was added as an option. In
accordance to it kubelet will generate resolv.conf based on own
resolv.conf. However, this doesn't create 'options', thus the proper
solution requires some investigation.
This patch sets the same resolv.conf for kubelet as host
Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>
Updates based on feedback
Simplify checks for file exists
remove invalid char
Review feedback. Use regular systemd file.
Add template for docker systemd atomic
* Leave all.yml to keep only optional vars
* Store groups' specific vars by existing group names
* Fix optional vars casted as mandatory (add default())
* Fix missing defaults for an optional IP var
* Relink group_vars for terraform to reflect changes
Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
Kubelet is responsible for creating symlinks from /var/lib/docker to /var/log
to make fluentd logging collector work.
However without using host's /var/log those links are invisible to fluentd.
This is done on rkt configuration too.
Since systemd kubelet.service has {{ ssl_ca_dirs }}, fact should be
gathered before writing kubelet.service.
Closes: #1007
Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>
- Exclude kubelet CPU/RAM (kube-reserved) from cgroup. It decreases a
chance of overcommitment
- Add a possibility to modify Kubelet node-status-update-frequency
- Add a posibility to configure node-monitor-grace-period,
node-monitor-period, pod-eviction-timeout for Kubernetes controller
manager
- Add Kubernetes Relaibility Documentation with recomendations for
various scenarios.
Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>
kubelet lost the ability to load kernel modules. This
puts that back by adding the lib/modules mount to kubelet.
The new variable kubelet_load_modules can be set to true
to enable this item. It is OFF by default.
- Docker 1.12 and further don't need nsenter hack. This patch removes
it. Also, it bumps the minimal version to 1.12.
Closes#776
Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>
* Drop linux capabilities for unprivileged containerized
worlkoads Kargo configures for deployments.
* Configure required securityContext/user/group/groups for kube
components' static manifests, etcd, calico-rr and k8s apps,
like dnsmasq daemonset.
* Rework cloud-init (etcd) users creation for CoreOS.
* Fix nologin paths, adjust defaults for addusers role and ensure
supplementary groups membership added for users.
* Add netplug user for network plugins (yet unused by privileged
networking containers though).
* Grant the kube and netplug users read access for etcd certs via
the etcd certs group.
* Grant group read access to kube certs via the kube cert group.
* Remove priveleged mode for calico-rr and run it under its uid/gid
and supplementary etcd_cert group.
* Adjust docs.
* Align cpu/memory limits and dropped caps with added rkt support
for control plane.
Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
* Add restart for weave service unit
* Reuse docker_bin_dir everythere
* Limit systemd managed docker containers by CPU/RAM. Do not configure native
systemd limits due to the lack of consensus in the kernel community
requires out-of-tree kernel patches.
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Also place in global vars and do not repeat the kube_*_config_dir
and kube_namespace vars for better code maintainability and UX.
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Fixes#655.
This is a teporary solution for long-polling idle connections to
apiserver. It will make Nginx not cut them for the duration of expected
timeout. It will also make Nginx extremely slow in realizing that there
is some issue with connectivity to apiserver as well, so it might not be
perfect permanent solution.
* Add dns_replicas, dns_memory/cpu_limit/requests vars for
dns related apps.
* When kube_log_level=4, log dnsmasq queries as well.
* Add log level control for skydns (part of kubedns app).
* Add limits/requests vars for dnsmasq (part of kubedns app) and
dnsmasq daemon set.
* Drop string defaults for kube_log_level as it is int and
is defined in the global vars as well.
* Add docs
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
According to http://kubernetes.io/docs/user-guide/images/ :
By default, the kubelet will try to pull each image from the
specified registry. However, if the imagePullPolicy property
of the container is set to IfNotPresent or Never, then a local\
image is used (preferentially or exclusively, respectively).
Use IfNotPresent value to allow images prepared by the download
role dependencies to be effectively used by kubelet without pull
errors resulting apps to stay blocked in PullBackOff/Error state
even when there are images on the localhost exist.
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
- Move CNI configuration from `kubernetes/node` role to
`network_plugin/canal`
- Create SSL dir for Canal and symlink etcd SSL files
- Add needed options to `canal-config` configmap
- Run flannel and calico-node containers with proper configuration
- Drop debugs from collect-info playbook
- Drop sudo from collect-info step and add target dir var (required for travis jobs)
- Label all k8s apps, including static manifests
- Add logs for K8s apps to be collected as well
- Fix upload to GCS as a public-read tarball
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Change the kubelet --hostname-override flag to use the ansible_hostname variable which should be more consistent with the value required by cloud providers
Add ansible_hostname alias to /etc/hosts when it is different from inventory_hostname to overcome node name limitations see https://github.com/kubernetes/kubernetes/issues/22770
Signed-off-by: Chad Swenson <chadswen@gmail.com>
The requirements for network policy feature are described here [1]. In
order to enable it, appropriate configuration must be provided to the CNI
plug in and Calico policy controller must be set up. Beside that
corresponding extensions needed to be enabled in k8s API.
Now to turn on the feature user can define `enable_network_policy`
customization variable for Ansible.
[1] http://kubernetes.io/docs/user-guide/networkpolicies/
Also adds all masters by hostname and localhost/127.0.0.1 to
apiserver SSL certificate.
Includes documentation update on how localhost loadbalancer works.
Change additional dnsmasq opts:
- Adjust caching size and TTL
- Disable resolve conf to not create loops
- Change dnsPolicy to default (similarly to kubedns's dnsmasq). The
ClusterFirst should not be used to not create loops
- Disable negative NXDOMAIN replies to be cached
- Make its very installation as optional step (enabled by default).
If you don't want more than 3 DNS servers, including 1 for K8s, disable
it.
- Add docs and a drawing to clarify DNS setup.
- Fix stdout logs for dnsmasq/kubedns app configs
- Add missed notifies to resolvconf -u handler
- Fix idempotency of resolvconf head file changes
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Creating the unit using default settings early on
and then changing it during network_plugin section
leads to too many docker restarts and duplicated code.
Reversed Wants= dependence on docker.service so it does not
restart docker when reloading systemd
Consolidated all docker restart handlers.
* Add for docker system units:
ExecReload=/bin/kill -s HUP $MAINPID
Delegate=yes
KillMode=process.
* Add missed DOCKER_OPTIONS for calico/weave docker systemd unit.
* Change Requires= to a less strict and non-faily Wants=, add missing
Wants= for After=.
* Align wants/after in a wat if Wants=foo, After= has foo as well.
* Make wants/after docker.service to ask for the docker.socket as well.
* Move "docker rm -f" commands from ExecStartPre= to ExecStopPost=.
hooks to ensure non-destructive start attempts issued by Wants=.
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
* Add HA docs for API server.
* Add auto-evaluated internal endpoints and clarify the loadbalancer_apiserver
vars and usecases.
* Use facts for kube_apiserver to not repeat code and enable LB endpoints use.
* Use /healthz check for the wait-for apiserver.
* Use the single endpoint for kubelet instead of the list of apiservers
* Specify kube_apiserver_count to for HA layout
Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
kubelet via docker
kube-apiserver as a static pod
Fixed etcd service start to be more tolerant of slow start.
Workaround for kube_version to stay in download role, but not
download an files by creating a new "nothing" download entry.
