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kubeadm: update implementation-details.md about CoreDNS #8829

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neolit123
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  • Replace examples from kube-dns to CoreDNS
  • Add notes about the CoreDNS feature gate status in 1.11

(list of other CoreDNS tasks / PRs)
Updates kubernetes/kubeadm#843

@rajansandeep , please have a look at some of the kube-dns->CoreDNS changes and verify if something doesn't apply to CoreDNS. thanks!

/assign @Bradamant3
/cc @kubernetes/sig-cluster-lifecycle-pr-reviews

@k8s-ci-robot k8s-ci-robot added sig/cluster-lifecycle Categorizes an issue or PR as relevant to SIG Cluster Lifecycle. cncf-cla: yes Indicates the PR's author has signed the CNCF CLA. labels May 31, 2018
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Deploy preview for kubernetes-io-vnext-staging processing.

Built with commit ff11985

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@k8s-ci-robot k8s-ci-robot added the size/S Denotes a PR that changes 10-29 lines, ignoring generated files. label May 31, 2018
@k8s-ci-robot k8s-ci-robot requested review from jbeda and luxas May 31, 2018 01:39
@Bradamant3 Bradamant3 added this to the 1.11 milestone May 31, 2018
- It's the upstream kube-dns deployment relatively unmodified
- The `kube-dns` ServiceAccount is bound to the privileges in the `system:kube-dns` ClusterRole
- It's the upstream CoreDNS deployment relatively unmodified
- The `kube-dns` ServiceAccount is bound to the privileges in the `system:coredns` ClusterRole
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@neolit123
s/kube-dns/coredns/

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@stealthybox
thanks! will update.

@@ -448,16 +448,18 @@ A ServiceAccount for `kube-proxy` is created in the `kube-system` namespace; the

#### DNS

A ServiceAccount for `kube-dns` is created in the `kube-system` namespace.
A ServiceAccount for `coredns` is created in the `kube-system` namespace.

Deploy the kube-dns Deployment and Service:
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s/kube-dns/coredns/

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s/coredns/CoreDNS

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@rajansandeep so this has to remain kube-dns as well?

@@ -448,16 +448,18 @@ A ServiceAccount for `kube-proxy` is created in the `kube-system` namespace; the

#### DNS

A ServiceAccount for `kube-dns` is created in the `kube-system` namespace.
A ServiceAccount for `coredns` is created in the `kube-system` namespace.

Deploy the kube-dns Deployment and Service:

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@neolit123 The CoreDNS service is named kube-dns.
Should we mention something like: "The CoreDNS service is named kube-dns. This is done to prevent any interruption in service when the user is switching the cluster DNS from kube-dns to CoreDNS or vice-versa."
@johnbelamaric what do you think?

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yikes..well it's confusing to say the least.
any plans to phase this out eventually?

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@neolit123 the naming has been kept on purpose. This prevents service loss when upgrading the cluster DNS.

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@rajansandeep ok, i will make an update, including the note possibly somewhere near the top of the page.

@neolit123 neolit123 force-pushed the kubeadm-implementation-details branch from c46c052 to ee96c27 Compare May 31, 2018 15:33
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@rajansandeep made updates. please have another look.

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/lgtm

@k8s-ci-robot k8s-ci-robot added the lgtm "Looks good to me", indicates that a PR is ready to be merged. label Jun 4, 2018
@mdlinville mdlinville force-pushed the kubeadm-implementation-details branch from ee96c27 to e4add33 Compare June 4, 2018 17:57
@k8s-ci-robot k8s-ci-robot removed the lgtm "Looks good to me", indicates that a PR is ready to be merged. label Jun 4, 2018
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I rebased to resolve conflicts.

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thanks @mistyhacks.

@mistyhacks, @Bradamant3 is this one good to go?

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Overall this file/topic is a bit confusing. It seems to have started out as a design document, but now it has bits of task content in it that probably belong elsewhere, or else need rephrasing as design explanations instead of tasks if the information is duplicated elsewhere. Flagging as part of larger kubeadm docs review; you don't need to worry about fixing up that part for this PR. But do make the requested copyedit changes. Thanks!

@@ -448,16 +448,19 @@ A ServiceAccount for `kube-proxy` is created in the `kube-system` namespace; the

#### DNS

A ServiceAccount for `kube-dns` is created in the `kube-system` namespace.
Please note that:
1. The CoreDNS service is named `kube-dns`. This is done to prevent any interruption
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In Hugo/Blackfriday, you need a space between the intro text ("Please note that:") and any sort of list. Also, remove "Please" bc it's information the user needs straight up. "Please" gets in the way.

Also, please make this into a bulleted list. It's not a series of steps in a procedure that must be performed in order. (Issue throughout the file, but I'm not asking you to fix it everywhere ;)).

(A usability note: it makes my head hurt to think about a service for CoreDNS being named the thing it's replacing as the default. This seems like confusing UX now, and possibly worse down the road. Are there any plans to fix up in a subsequent release?)

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@rajansandeep

(A usability note: it makes my head hurt to think about a service for CoreDNS being named the thing it's replacing as the default. This seems like confusing UX now, and possibly worse down the road. Are there any plans to fix up in a subsequent release?)

do you know the roadmap for the above?

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You can't change that without potential down time. name and ClusterIP are immutable on Services, and you can't use the same ClusterIP for two services. So, they only way to fix it is to actually lose DNS service for a very short window. we decided in sig-network that the service name refers to the service, regardless of the specific implementation that is providing the service.

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@neolit123 this will remain until kube-dns and CoreDNS are both available to install. This can change once kube-dns is deprecated eventually, but for the time being there is no plan to change this.

@johnbelamaric

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@johnbelamaric @rajansandeep thanks for the details.
@Bradamant3 we have to keep this note. i will now fix the rest of the text formatting issues.

Please note that:
1. The CoreDNS service is named `kube-dns`. This is done to prevent any interruption
in service when the user is switching the cluster DNS from kube-dns to CoreDNS or vice-versa.
2. In Kubernetes version 1.11 and later, CoreDNS has become the default DNS server and you have to
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s/has become/is
s/have to/must

(stronger clearer language)

in service when the user is switching the cluster DNS from kube-dns to CoreDNS or vice-versa.
2. In Kubernetes version 1.11 and later, CoreDNS has become the default DNS server and you have to
invoke kubeadm with `--feature-gates=CoreDNS=false` to install kube-dns instead.
3. In Kubernetes versions prior to 1.11, CoreDNS has to be enabled with `--feature-gates=CoreDNS=true`.
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Keep this parallel to the previous item, and reword thus:
"In Kubernetes version 1.10 and earlier, you must enable CoreDNS with --feature-gates=CoreDNS=true."

- Replace examples from kube-dns to CoreDNS
- Add notes about the CoreDNS feature gate status in 1.11
- Add note that the service name for CoreDNS is also
called `kube-dns`
@neolit123 neolit123 force-pushed the kubeadm-implementation-details branch from e4add33 to ff11985 Compare June 5, 2018 19:37
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@Bradamant3
PR updated and rebased.

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re-adding lgtm because tech review already approved; was lost bc copyedits

/lgtm
/approve

@k8s-ci-robot k8s-ci-robot added the lgtm "Looks good to me", indicates that a PR is ready to be merged. label Jun 6, 2018
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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Bradamant3

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@k8s-ci-robot k8s-ci-robot added the approved Indicates a PR has been approved by an approver from all required OWNERS files. label Jun 6, 2018
@k8s-ci-robot k8s-ci-robot merged commit 097d08a into kubernetes:release-1.11 Jun 6, 2018
mdlinville pushed a commit that referenced this pull request Jun 20, 2018
- Replace examples from kube-dns to CoreDNS
- Add notes about the CoreDNS feature gate status in 1.11
- Add note that the service name for CoreDNS is also
called `kube-dns`
mdlinville pushed a commit that referenced this pull request Jun 27, 2018
- Replace examples from kube-dns to CoreDNS
- Add notes about the CoreDNS feature gate status in 1.11
- Add note that the service name for CoreDNS is also
called `kube-dns`
mdlinville pushed a commit that referenced this pull request Jun 27, 2018
- Replace examples from kube-dns to CoreDNS
- Add notes about the CoreDNS feature gate status in 1.11
- Add note that the service name for CoreDNS is also
called `kube-dns`
k8s-ci-robot pushed a commit that referenced this pull request Jun 27, 2018
* Seperate priority and preemption (#8144)

* Doc about PID pressure condition. (#8211)

* Doc about PID pressure condition.

Signed-off-by: Da K. Ma <klaus1982.cn@gmail.com>

* "so" -> "too"

* Update version selector for 1.11

* StorageObjectInUseProtection is GA (#8291)

* Feature gate: StorageObjectInUseProtection is GA

Update feature gate reference for 1.11

* Trivial commit to re-trigger Netlify

* CRIContainerLogRotation is Beta in 1.11 (#8665)

* Seperate priority and preemption (#8144)

* CRIContainerLogRotation is Beta in 1.11

xref: kubernetes/kubernetes#64046

* Bring StorageObjectInUseProtection feature to GA (#8159)

* StorageObjectInUseProtection is GA (#8291)

* Feature gate: StorageObjectInUseProtection is GA

Update feature gate reference for 1.11

* Trivial commit to re-trigger Netlify

* Bring StorageObjectInUseProtection feature to GA

StorageObjectInUseProtection is Beta in K8s 1.10.

It's brought to GA in K8s 1.11.

* Fixed typo and added feature state tags.

* Remove KUBE_API_VERSIONS doc (#8292)

The support to the KUBER_API_VERSIONS environment variable is completely
dropped (no deprecation). This PR removes the related doc in
release-1.11.

xref: kubernetes/kubernetes#63165

* Remove InitialResources from admission controllers (#8293)

The feature (was experimental) is dropped in 1.11.

xref: kubernetes/kubernetes#58784

* Remove docs related to in-tree support to GPU (#8294)

* Remove docs related to in-tree support to GPU

The in-tree support to GPU is completely removed in release 1.11.
This PR removes the related docs in release-1.11 branch.

xref: kubernetes/kubernetes#61498

* Update content updated by PR to Hugo syntax

Signed-off-by: Misty Stanley-Jones <mistyhacks@google.com>

* Update the doc about extra volume in kubeadm config (#8453)

Signed-off-by: Xianglin Gao <xianglin.gxl@alibaba-inc.com>

* Update CRD Subresources for 1.11 (#8519)

* coredns: update notes in administer-cluster/coredns.md (#8697)

CoreDNS is installed by default in 1.11.
Add notes on how to install kube-dns instead.

Update notes about CoreDNS->CoreDNS upgrades as in 1.11
the Corefile is retained.

Add example on upgrading from kube-dns to CoreDNS.

* kubeadm-alpha: CoreDNS related changes (#8727)

Update note about CoreDNS feature gate.

This change also updates a tab as a kubeadm sub-command
will change.

It looks for a new generated file:
generated/kubeadm_alpha_phase_addon_coredns.md
instead of:
generated/kubeadm_alpha_phase_addon_kube-dns.md

* Update cloud controller manager docs to beta 1.11 (#8756)

* Update cloud controller manager docs to beta 1.11

* Use Hugo shortcode for feature state

* kubeadm-upgrade: include new command `kubeadm upgrade diff` (#8617)

Also:
- Include note that this was added in 1.11.
- Modify the note about upgrade guidance.

* independent: update CoreDNS mentions for kubeadm (#8753)

Give CoreDNS instead of kube-dns examples in:
- docs/setup/independent/create-cluster-kubeadm.md
- docs/setup/independent/troubleshooting-kubeadm.md

* update 1.11 --server-print info (#8870)

* update 1.11 --server-print info

* Copyedit

* Mark ExpandPersistentVolumes feature to beta (#8778)

* Update version selector for 1.11

* Mark ExpandPersistentVolumes Beta

xref: kubernetes/kubernetes#64288

* fix shortcode, add placeholder files to fix deploy failures (#8874)

* declare ipvs ga (#8850)

* kubeadm: update info about CoreDNS in kubeadm-init.md (#8728)

Add info to install kube-dns instead of CoreDNS, as CoreDNS
is the default DNS server in 1.11.

Add notes that kubeadm config images can be used to list and pull
the required images in 1.11.

* kubeadm: update implementation-details.md about CoreDNS (#8829)

- Replace examples from kube-dns to CoreDNS
- Add notes about the CoreDNS feature gate status in 1.11
- Add note that the service name for CoreDNS is also
called `kube-dns`

* Update block device support for 1.11 (#8895)

* Update block device support for 1.11

* Copyedits

* Fix typo 'fiber channel' (#8957)

Signed-off-by: Misty Stanley-Jones <mistyhacks@google.com>

* kubeadm-upgrade: add the 'node [config]' sub-command (#8960)

- Add includes for the generated pages
- Include placeholder generated pages

* kubeadm-init: update the example for the MasterConfiguration (#8958)

- include godocs link for MasterConfiguration
- include example MasterConfiguration
- add note that `kubeadm config print-default` can be used

* kubeadm-config: include new commands (#8862)

Add notes and includes for these new commands in 1.11:
- kubeadm config print-default
- kubeadm config migrate
- kubeadm config images list
- kubeadm config images pull

Include placeholder generated files for the above.

* administer-cluster/coredns: include more changes (#8985)

It was requested that for this page a couple of methods
should be outlined:
- manual installation for CoreDNS explained at the Kubernetes
section of the GitHub project for CoreDNS
- installation and upgrade via kubeadm

Make the above changes and also add a section "About CoreDNS".

This commit also lowercases a section title.

* Update CRD subresources doc for 1.11 (#8918)

* Add docs for volume expansion and online resizing (#8896)

* Add docs for volume expansion going beta

* Copyedit

* Address feedback

* Update exec plugin docs with TLS credentials (#8826)

* Update exec plugin docs with TLS credentials

kubernetes/kubernetes#61803 implements TLS client credential support for
1.11.

* Copyedit

* More copyedits for clarification

* Additional copyedit

* Change token->credential

* NodeRestriction admission prevents kubelet taint removal (#8911)

* dns-custom-namerserver: break down the page into mutliple sections (#8900)

* dns-custom-namerserver: break down the page into mutliple sections

This page is currently about kube-dns and is a bit outdated.
Introduce the heading `# Customizing kube-dns`.

Introduce a separate section about CoreDNS.

* Copyedits, fix headings for customizing DNS

Hey Lubomir,
I coypedited pretty heavily because this workflow is so much easier for docs and because I'm trying to help improve everything touching kubeadm as much as possible.

But there's one outstanding issue wrt headings and intro content: you can't add a heading 1 to a topic to do what you wanted to do. The page title in the front matter is rendered as a heading 1 and everything else has to start at heading 2. (We still need to doc this better in the docs contributing content, I know.)

Instead, I think we need to rewrite the top-of-page intro content to explain better the relationship between kube-dns and CoreDNS. I'm happy to write something, but I thought I'd push this commit first so you can see what I'm doing.

Hope it's all clear -- ping here or on Slack with any questions ~ Jennifer

* Interim fix for talking about CoreDNS

* Fix CoreDNS details

* PSP readOnly hostPath (#8898)

* Add documentation for crictl (#8880)

* Add documentation for crictl

* Copyedit

Signed-off-by: Misty Stanley-Jones <mistyhacks@google.com>

* Final copyedit

* VolumeSubpathEnvExpansion alpha feature (#8835)

* Note that Heapster is deprecated (#8827)

* Note that Heapster is deprecated

This notes that Heapster is deprecated, and migrates the relevant
docs to talk about metrics-server or other solutions by default.

* Copyedits and improvements

Signed-off-by: Misty Stanley-Jones <mistyhacks@google.com>

* Address feedback

* fix shortcode to troubleshoot deploy (#9057)

* update dynamic kubelet config docs for v1.11 (#8766)

* update dynamic kubelet config docs for v1.11

* Substantial copyedit

* Address feedback

* Reference doc for kubeadm (release-1.11) (#9044)

* Reference doc for kubeadm (release-1.11)

* fix shortcode to troubleshoot deploy (#9057)

* Reference doc for kube-components (release-1.11) (#9045)

* Reference doc for kube-components (release-1.11)

* Update cloud-controller-manager.md

* fix shortcode to troubleshoot deploy (#9057)

* Documentation on lowercasing kubeadm init apiserver SANs (#9059)

* Documentation on lowercasing kubeadm init apiserver SANs

* fix shortcode to troubleshoot deploy (#9057)

* Clarification in dynamic Kubelet config doc (#9061)

* Promote sysctls to Beta (#8804)

* Promote sysctls to Beta

* Copyedits

Signed-off-by: Misty Stanley-Jones <mistyhacks@google.com>

* Review comments

* Address feedback

* More feedback

* kubectl reference docs for 1.11 (#9080)

* Update Kubernetes API 1.11 ref docs (#8977)

* Update v1alpha1 to v1beta1.

* Adjust left nav for 1.11 ref docs.

* Trim list of old ref docs.

* Update Federation API ref docs for 1.11. (#9064)

* Update Federation API ref docs for 1.11.

* Add titles.

* Update definitions.html

* CRD versioning Public Documentation (#8834)

* CRD versioning Public Documentation

* Copyedit

Signed-off-by: Misty Stanley-Jones <mistyhacks@google.com>

* Address feedback

* More rewrites

* Address feedback

* Update main CRD page in light of versioning

* Reorg CRD docs

* Further reorg

* Tweak title

* CSI documentation update for raw block volume support (#8927)

* CSI documetation update for raw block volume support

* minor edits for "CSI raw block volume support"

Some small grammar and style nits.

* minor CSIBlockVolume edits

* Update kubectl component ref page for 1.11. (#9094)

* Update kubectl component ref page for 1.11.

* Add title. Replace stevepe with username.

* crd versioning doc: fix nits (#9142)

* Update `DynamicKubeletConfig` feature to beta (#9110)

xref: kubernetes/kubernetes#64275

* Documentation for dynamic volume limits based on node type (#8871)

* add cos for storage limits

* Update docs specific for aws and gce

* fix some minor things

* Update storage-limits.md

* Add k8s version to feature-state shortcode

* The Doc update for ScheduleDaemonSetPods (#8842)

Signed-off-by: Da K. Ma <klaus1982.cn@gmail.com>

* Update docs related to PersistentVolumeLabel admission control (#9109)

The said admission controller is disabled by default in 1.11
(kubernetes/kubernetes#64326) and scheduled to be removed in future
release.

* client exec auth: updates for 1.11 (#9154)

* Updates HA kubeadm docs (#9066)

* Updates HA kubeadm docs

Signed-off-by: Chuck Ha <ha.chuck@gmail.com>

* kubeadm HA - Add stacked control plane steps

* ssh instructions and some typos in the bash scripts

Signed-off-by: Chuck Ha <ha.chuck@gmail.com>

* Fix typos and copypasta errors

* Fix rebase issues

* Integrate more changes

Signed-off-by: Chuck Ha <ha.chuck@gmail.com>

* copyedits, layout and formatting fixes

* final copyedits

* Adds a sanity check for load balancer connection

Signed-off-by: Chuck Ha <ha.chuck@gmail.com>

* formatting fixes, copyedits

* fix typos, formatting

* Document the Pod Ready++ feature (#9180)

Closes: #9107
Xref: kubernetes/kubernetes#64057

* Mention 'KubeletPluginsWatcher' feature (#9177)

* Mention 'KubeletPluginsWatcher' feature

This feature is more developers oriented than users oriented, so simply
mention it in the feature gate should be fine.
In future, when the design doc is migrated from Google doc to the
kubernetes/community repo, we can add links to it for users who want to
dig deeper.

Closes: #9108
Xref: kubernetes/kubernetes#63328, kubernetes/kubernetes#64605

* Copyedit

* Amend dynamic volume list docs (#9181)

The dynamic volume list feature has been documented but the feature gate
related was not there yet.

Closes: #9105

* Document for service account projection (#9182)

This adds docs for the service account projection feature.

Xref: kubernetes/kubernetes#63819, kubernetes/community#1973
Closes: #9102

* Update pod priority and preemption user docs (#9172)

* Update pod priority and preemption user docs

* Copyedit

* Documentation on setting node name with Kubeadm (#8925)

* Documentation on setting node name with Kubeadm

* copyedit

* Add kubeadm upgrade docs for 1.11 (#9089)

* Add kubeadm upgrade docs for 1.11

* Initial docs review feedback

* Add 1-11 to outline

* Fix formatting on tab blocks

* Move file to correct location

* Add `kubeadm upgrade node config` step

* Overzealous ediffing

* copyedit, fix lists and headings

* clarify --force flag for fixing bad state

* Get TOML ready for 1.11 release

* Blog post for 1.11 release (#9254)

* Blog post for 1.11 release

* Update 2018-06-26-kubernetes-1.11-release-announcement.md

* Update 2018-06-26-kubernetes-1.11-release-announcement.md

* Update 2018-06-26-kubernetes-1.11-release-announcement.md
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