Merge pull request #33993 from kinzhi/kinzhi130
[zh]Update content/zh/docs/concepts/services-networking/dns-pod-service.mdpull/34038/head
Kubernetes Prow Robot
GitHub
commit
c41e6e4ba8
|
|
@ -37,27 +37,27 @@ Kubernetes DNS 在集群上调度 DNS Pod 和服务，并配置 kubelet 以告
|
|||
|
||||
<!--
|
||||
Every Service defined in the cluster (including the DNS server itself) is
|
||||
assigned a DNS name. By default, a client Pod's DNS search list includes the
|
||||
Pod's own namespace and the cluster's default domain.
|
||||
assigned a DNS name. By default, a client Pod's DNS search list includes the
|
||||
Pod's own namespace and the cluster's default domain.
|
||||
-->
|
||||
集群中定义的每个 Service （包括 DNS 服务器自身）都被赋予一个 DNS 名称。
|
||||
默认情况下，客户端 Pod 的 DNS 搜索列表会包含 Pod 自身的名字空间和集群
|
||||
的默认域。
|
||||
|
||||
<!--
|
||||
### Namespaces of Services
|
||||
### Namespaces of Services
|
||||
|
||||
A DNS query may return different results based on the namespace of the pod making
|
||||
it. DNS queries that don't specify a namespace are limited to the pod's
|
||||
namespace. Access services in other namespaces by specifying it in the DNS query.
|
||||
A DNS query may return different results based on the namespace of the pod making
|
||||
it. DNS queries that don't specify a namespace are limited to the pod's
|
||||
namespace. Access services in other namespaces by specifying it in the DNS query.
|
||||
|
||||
For example, consider a pod in a `test` namespace. A `data` service is in
|
||||
the `prod` namespace.
|
||||
For example, consider a pod in a `test` namespace. A `data` service is in
|
||||
the `prod` namespace.
|
||||
|
||||
A query for `data` returns no results, because it uses the pod's `test` namespace.
|
||||
A query for `data` returns no results, because it uses the pod's `test` namespace.
|
||||
|
||||
A query for `data.prod` returns the intended result, because it specifies the
|
||||
namespace.
|
||||
A query for `data.prod` returns the intended result, because it specifies the
|
||||
namespace.
|
||||
-->
|
||||
### Service 的名字空间
|
||||
|
||||
|
|
@ -73,11 +73,11 @@ Pod 查询 `data` 时没有返回结果，因为使用的是 Pod 的名字空间
|
|||
Pod 查询 `data.prod` 时则会返回预期的结果，因为查询中指定了名字空间。
|
||||
|
||||
<!--
|
||||
DNS queries may be expanded using the pod's `/etc/resolv.conf`. Kubelet
|
||||
sets this file for each pod. For example, a query for just `data` may be
|
||||
expanded to `data.test.cluster.local`. The values of the `search` option
|
||||
are used to expand queries. To learn more about DNS queries, see
|
||||
[the `resolv.conf` manual page.](https://www.man7.org/linux/man-pages/man5/resolv.conf.5.html)
|
||||
DNS queries may be expanded using the pod's `/etc/resolv.conf`. Kubelet
|
||||
sets this file for each pod. For example, a query for just `data` may be
|
||||
expanded to `data.test.svc.cluster.local`. The values of the `search` option
|
||||
are used to expand queries. To learn more about DNS queries, see
|
||||
[the `resolv.conf` manual page.](https://www.man7.org/linux/man-pages/man5/resolv.conf.5.html)
|
||||
-->
|
||||
DNS 查询可以使用 Pod 中的 `/etc/resolv.conf` 展开。kubelet 会为每个 Pod
|
||||
生成此文件。例如，对 `data` 的查询可能被展开为 `data.test.svc.cluster.local`。
|
||||
|
|
@ -91,7 +91,7 @@ options ndots:5
|
|||
```
|
||||
|
||||
<!--
|
||||
In summary, a pod in the _test_ namespace can successfully resolve either
|
||||
In summary, a pod in the _test_ namespace can successfully resolve either
|
||||
`data.prod` or `data.prod.svc.cluster.local`.
|
||||
-->
|
||||
概括起来，名字空间 `test` 中的 Pod 可以成功地解析 `data.prod` 或者
|
||||
|
|
@ -127,12 +127,14 @@ For more up-to-date specification, see
|
|||
|
||||
### A/AAAA records
|
||||
|
||||
"Normal" (not headless) Services are assigned a DNS A or AAAA record for a name of the
|
||||
form `my-svc.my-namespace.svc.cluster-domain.example`. This resolves to the cluster IP
|
||||
"Normal" (not headless) Services are assigned a DNS A or AAAA record,
|
||||
depending on the IP family of the service, for a name of the form
|
||||
`my-svc.my-namespace.svc.cluster-domain.example`. This resolves to the cluster IP
|
||||
of the Service.
|
||||
|
||||
"Headless" (without a cluster IP) Services are also assigned a DNS A record for
|
||||
a name of the form `my-svc.my-namespace.svc.cluster-domain.example`. Unlike normal
|
||||
"Headless" (without a cluster IP) Services are also assigned a DNS A or AAAA record,
|
||||
depending on the IP family of the service, for a name of the form
|
||||
`my-svc.my-namespace.svc.cluster-domain.example`. Unlike normal
|
||||
Services, this resolves to the set of IPs of the pods selected by the Service.
|
||||
Clients are expected to consume the set or else use standard round-robin
|
||||
selection from the set.
|
||||
|
|
@ -314,9 +316,9 @@ along with its IP.
|
|||
Endpoints 对象可以为任何端点地址及其 IP 指定 `hostname`。
|
||||
|
||||
<!--
|
||||
Because A records are not created for Pod names, `hostname` is required for the Pod's A
|
||||
Because A or AAAA records are not created for Pod names, `hostname` is required for the Pod's A or AAAA
|
||||
record to be created. A Pod with no `hostname` but with `subdomain` will only create the
|
||||
A record for the headless service (`default-subdomain.my-namespace.svc.cluster-domain.example`),
|
||||
A or AAAA record for the headless service (`default-subdomain.my-namespace.svc.cluster-domain.example`),
|
||||
pointing to the Pod's IP address. Also, Pod needs to become ready in order to have a
|
||||
record unless `publishNotReadyAddresses=True` is set on the Service.
|
||||
-->
|
||||
|
|
@ -341,12 +343,13 @@ record unless `publishNotReadyAddresses=True` is set on the Service.
|
|||
{{< feature-state for_k8s_version="v1.22" state="stable" >}}
|
||||
|
||||
<!--
|
||||
When a Pod is configured to have fully qualified domain name (FQDN), its hostname is the short hostname. For example, if you have a Pod with the fully qualified domain name `busybox-1.default-subdomain.my-namespace.svc.cluster-domain.example`, then by default the `hostname` command inside that Pod returns `busybox-1` and the `hostname -fqdn` command returns the FQDN.
|
||||
When a Pod is configured to have fully qualified domain name (FQDN), its hostname is the short hostname. For example, if you have a Pod with the fully qualified domain name `busybox-1.default-subdomain.my-namespace.svc.cluster-domain.example`, then by default the `hostname` command inside that Pod returns `busybox-1` and the `hostname --fqdn` command returns the FQDN.
|
||||
|
||||
When you set `setHostnameAsFQDN: true` in the Pod spec, the kubelet writes the Pod's FQDN into the hostname for that Pod's namespace. In this case, both `hostname` and `hostname --fqdn` return the Pod's FQDN.
|
||||
-->
|
||||
**前置条件**：`SetHostnameAsFQDN`
|
||||
[特性门控](/zh/docs/reference/command-line-tools-reference/feature-gates/)
|
||||
必须在 {{< glossary_tooltip text="API 服务器" term_id="kube-apiserver" >}}
|
||||
上启用。
|
||||
当 Pod 配置为具有全限定域名 (FQDN) 时，其主机名是短主机名。
|
||||
例如，如果你有一个具有完全限定域名 `busybox-1.default-subdomain.my-namespace.svc.cluster-domain.example` 的 Pod，
|
||||
则默认情况下，该 Pod 内的 `hostname` 命令返回 `busybox-1`，而 `hostname --fqdn` 命令返回 FQDN。
|
||||
|
||||
当你在 Pod 规约中设置了 `setHostnameAsFQDN: true` 时，kubelet 会将 Pod
|
||||
的全限定域名（FQDN）作为该 Pod 的主机名记录到 Pod 所在名字空间。
|
||||
|
|
@ -392,10 +395,11 @@ following pod-specific DNS policies. These policies are specified in the
|
|||
for details on how DNS queries are handled in those cases.
|
||||
- "`ClusterFirstWithHostNet`": For Pods running with hostNetwork, you should
|
||||
explicitly set its DNS policy "`ClusterFirstWithHostNet`".
|
||||
- Note: This is not supported on Windows. See [below](#dns-windows) for details
|
||||
- "`None`": It allows a Pod to ignore DNS settings from the Kubernetes
|
||||
environment. All DNS settings are supposed to be provided using the
|
||||
`dnsConfig` field in the Pod Spec.
|
||||
See [Pod's DNS config](#pod-s-dns-config) subsection below.
|
||||
See [Pod's DNS config](#pod-dns-config) subsection below.
|
||||
-->
|
||||
### Pod 的 DNS 策略 {#pod-s-dns-policy}
|
||||
|
||||
|
|
@ -411,6 +415,7 @@ DNS 策略可以逐个 Pod 来设定。目前 Kubernetes 支持以下特定 Pod
|
|||
了解在这些场景中如何处理 DNS 查询的信息。
|
||||
- "`ClusterFirstWithHostNet`"：对于以 hostNetwork 方式运行的 Pod，应显式设置其 DNS 策略
|
||||
"`ClusterFirstWithHostNet`"。
|
||||
- 注意：这在 Windows 上不支持。 有关详细信息，请参见[下文](#dns-windows)。
|
||||
- "`None`": 此设置允许 Pod 忽略 Kubernetes 环境中的 DNS 设置。Pod 会使用其 `dnsConfig` 字段
|
||||
所提供的 DNS 设置。
|
||||
参见 [Pod 的 DNS 配置](#pod-dns-config)节。
|
||||
|
|
@ -450,7 +455,7 @@ spec:
|
|||
```
|
||||
|
||||
<!--
|
||||
### Pod's DNS Config
|
||||
### Pod's DNS Config {#pod-dns-config}
|
||||
|
||||
{{< feature-state for_k8s_version="v1.14" state="stable" >}}
|
||||
|
||||
|
|
@ -535,8 +540,7 @@ kubectl exec -it dns-example -- cat /etc/resolv.conf
|
|||
<!--
|
||||
The output is similar to this:
|
||||
-->
|
||||
输出类似于
|
||||
|
||||
输出类似于：
|
||||
```
|
||||
nameserver fd00:79:30::a
|
||||
search default.svc.cluster-domain.example svc.cluster-domain.example cluster-domain.example
|
||||
|
|
@ -565,6 +569,42 @@ a list of search domains of up to 2048 characters.
|
|||
如果启用 kube-apiserver 和 kubelet 的特性门控 `ExpandedDNSConfig`，Kubernetes 将可以有最多 32 个
|
||||
搜索域以及一个最多 2048 个字符的搜索域列表。
|
||||
|
||||
<!--
|
||||
## DNS resolution on Windows nodes {#dns-windows}
|
||||
-->
|
||||
## Windows 节点上的 DNS 解析 {#dns-windows}
|
||||
|
||||
<!--
|
||||
- ClusterFirstWithHostNet is not supported for pods that run on Windows nodes.
|
||||
Windows treats all names with a `.` as a FQDN and skips FQDN resolution.
|
||||
- On Windows, there are multiple DNS resolvers that can be used. As these come with
|
||||
slightly different behaviors, using the
|
||||
[`Resolve-DNSName`](https://docs.microsoft.com/powershell/module/dnsclient/resolve-dnsname)
|
||||
powershell cmdlet for name query resolutions is recommended.
|
||||
- On Linux, you have a DNS suffix list, which is used after resolution of a name as fully
|
||||
qualified has failed.
|
||||
On Windows, you can only have 1 DNS suffix, which is the DNS suffix associated with that
|
||||
pod's namespace (example: `mydns.svc.cluster.local`). Windows can resolve FQDNs, services,
|
||||
or network name which can be resolved with this single suffix. For example, a pod spawned
|
||||
in the `default` namespace, will have the DNS suffix `default.svc.cluster.local`.
|
||||
Inside a Windows pod, you can resolve both `kubernetes.default.svc.cluster.local`
|
||||
and `kubernetes`, but not the partially qualified names (`kubernetes.default` or
|
||||
`kubernetes.default.svc`).
|
||||
-->
|
||||
- 在 Windows 节点上运行的 Pod 不支持 ClusterFirstWithHostNet。
|
||||
Windows 将所有带有 `.` 的名字视为 FQDN 并跳过 FQDN 解析。
|
||||
- 在 Windows 上，可以使用多个 DNS 解析器。由于这些解析器的行为上略有不同，建议使用
|
||||
[`Resolve-DNSName`](https://docs.microsoft.com/powershell/module/dnsclient/resolve-dnsname)
|
||||
这个 PowerShell cmdlet 进行名字查询解析。
|
||||
- 在 Linux 上，你会有一个 DNS 后缀列表，在全限定域名解析失败之后会使用这里的后缀。
|
||||
在 Windows 上，你只能有 1 个 DNS 后缀，即与 Pod 的命名空间关联的 DNS
|
||||
后缀（例如：`mydns.svc.cluster.local`）。 Windows 可以解析能够使用此唯一后缀解析的
|
||||
FQDN、服务与网络名字。
|
||||
例如，在 `default` 命名空间中产生的某个 Pod 将具有 DNS 后缀 `default.svc.cluster.local`。
|
||||
在 Windows Pod 中，你可以解析 `kubernetes.default.svc.cluster.local`
|
||||
和 `kubernetes`，但无法解析部分限定名称（`kubernetes.default` 或
|
||||
`kubernetes.default.svc`）。
|
||||
|
||||
## {{% heading "whatsnext" %}}
|
||||
|
||||
<!--
|
||||
|
|
|
|||
Loading…
Reference in New Issue