网络策略
This commit is contained in:
95
learning/k8s-intermediate/service/np-default.md
Normal file
95
learning/k8s-intermediate/service/np-default.md
Normal file
@ -0,0 +1,95 @@
|
||||
---
|
||||
vssueId: 158
|
||||
layout: LearningLayout
|
||||
description: Kubernetes中_网络策略定义了一组Pod是否允许相互通信_或者与网络中的其他端点endpoint通信_本文描述了K8S集群中默认的网络策略
|
||||
meta:
|
||||
- name: keywords
|
||||
content: Kubernetes教程,K8S教程,Kubernetes Network Policies, K8S 网络策略
|
||||
---
|
||||
|
||||
# Network Policies - Default
|
||||
|
||||
<AdSenseTitle>
|
||||
|
||||
> 参考文档: [Network Policies](https://kubernetes.io/docs/concepts/services-networking/network-policies/)
|
||||
|
||||
默认情况下,如果名称空间中没有配置 NetworkPolicy,则该名称空间中,所有Pod的所有入方向流量和所有出方向流量都是被允许的。本文列举了几个例子,可以用来改变名称空间中默认的网络策略
|
||||
|
||||
</AdSenseTitle>
|
||||
|
||||
## 默认拒绝所有的入方向流量
|
||||
|
||||
在名称空间中创建下面的 NetworkPolicy,该 NetworkPolicy:
|
||||
* 选中所有的 Pod
|
||||
* 不允许任何入方向的流量
|
||||
|
||||
``` yaml
|
||||
apiVersion: networking.k8s.io/v1
|
||||
kind: NetworkPolicy
|
||||
metadata:
|
||||
name: default-deny
|
||||
spec:
|
||||
podSelector: {}
|
||||
policyTypes:
|
||||
- Ingress
|
||||
```
|
||||
|
||||
此 NetworkPolicy 将确保名称空间中所有的入方向流量都被限制,同时,不改变出方向的流量。
|
||||
|
||||
## 默认允许所有的入方向流量
|
||||
|
||||
在名称空间中创建下面的 NetworkPolicy,该 NetworkPolicy 允许名称空间中所有 Pod 的所有入方向网络流量
|
||||
|
||||
``` yaml
|
||||
apiVersion: networking.k8s.io/v1
|
||||
kind: NetworkPolicy
|
||||
metadata:
|
||||
name: allow-all
|
||||
spec:
|
||||
podSelector: {}
|
||||
ingress:
|
||||
- {}
|
||||
policyTypes:
|
||||
- Ingress
|
||||
```
|
||||
|
||||
## 默认拒绝所有出方向流量
|
||||
|
||||
在名称空间中创建下面的 NetworkPolicy,该 NetworkPolicy 禁止名称空间中所有 Pod 的所有出方向网络流量
|
||||
|
||||
``` yaml
|
||||
apiVersion: networking.k8s.io/v1
|
||||
kind: NetworkPolicy
|
||||
metadata:
|
||||
name: allow-all
|
||||
spec:
|
||||
podSelector: {}
|
||||
egress:
|
||||
- {}
|
||||
policyTypes:
|
||||
- Egress
|
||||
```
|
||||
|
||||
## 默认拒绝所有入方向和出方向的网络流量
|
||||
|
||||
在名称空间中创建下面的 NetworkPolicy,该 NetworkPolicy 禁止名称空间中所有 Pod 的所有入方向流量和所有出方向流量
|
||||
|
||||
``` yaml
|
||||
apiVersion: networking.k8s.io/v1
|
||||
kind: NetworkPolicy
|
||||
metadata:
|
||||
name: default-deny
|
||||
spec:
|
||||
podSelector: {}
|
||||
policyTypes:
|
||||
- Ingress
|
||||
- Egress
|
||||
```
|
||||
|
||||
## SCTP 支持
|
||||
|
||||
**FEATURE STATE:** `Kubernetes v1.12` <Badge type="danger">alpha</Badge>
|
||||
|
||||
在 Kubernetes 中启用 `SCTPSupport` 特性,可以在 `NetworkPolicy` 的 `protocal` 字段中使用 SCTP 这个选项,该特性为 alpha 状态。向 apiserver 的启动参数中添加 `--feature-gates=SCTPSupport=true,...` 可以激活该特性。
|
||||
|
||||
使用此特性时,您所用的网络插件需要支持 SCTP,请查询网络插件相关的文档。
|
||||
145
learning/k8s-intermediate/service/np-example.md
Normal file
145
learning/k8s-intermediate/service/np-example.md
Normal file
@ -0,0 +1,145 @@
|
||||
---
|
||||
vssueId: 158
|
||||
layout: LearningLayout
|
||||
description: Kubernetes中_网络策略定义了一组Pod是否允许相互通信_或者与网络中的其他端点endpoint通信_本文描述了几个在K8S集群的名称空间中创建NetworkPolicy的例子
|
||||
meta:
|
||||
- name: keywords
|
||||
content: Kubernetes教程,K8S教程,Kubernetes Network Policies, K8S 网络策略
|
||||
---
|
||||
|
||||
# Network Policies - Example
|
||||
|
||||
<AdSenseTitle>
|
||||
|
||||
> 参考文档: [Declare Network Policy](https://kubernetes.io/docs/tasks/administer-cluster/declare-network-policy/)
|
||||
|
||||
本文描述了如何在 Kubernetes 集群中通过创建 NetworkPolicy 的方式来声明网络策略,以管理 Pod 之间的网络通信流量。
|
||||
|
||||
[[TOC]]
|
||||
|
||||
</AdSenseTitle>
|
||||
|
||||
## 前提条件
|
||||
|
||||
您已经安装了 Kubernetes 集群,如果没有,请参考文档 [安装Kubernetes单Master节点](/install/install-k8s.html)
|
||||
|
||||
您可以使用 kubectl 访问您的集群,请参考文档 [安装Kubectl](/install/install-kubectl.html)
|
||||
|
||||
请确保您使用的网络插件支持 Network Policy,如下的网络插件都是可以的:
|
||||
|
||||
* [Calico](https://kubernetes.io/docs/tasks/administer-cluster/network-policy-provider/calico-network-policy/) 如果您按照 [安装Kubernetes单Master节点](/install/install-k8s.html) 安装的集群,默认是 calico 网络插件
|
||||
* [Cilium](https://kubernetes.io/docs/tasks/administer-cluster/network-policy-provider/cilium-network-policy/)
|
||||
* [Kube-router](https://kubernetes.io/docs/tasks/administer-cluster/network-policy-provider/kube-router-network-policy/)
|
||||
* [Romana](https://kubernetes.io/docs/tasks/administer-cluster/network-policy-provider/romana-network-policy/)
|
||||
* [Weave Net](https://kubernetes.io/docs/tasks/administer-cluster/network-policy-provider/weave-network-policy/)
|
||||
|
||||
::: tip
|
||||
按字母顺序排序,不代表推荐顺序。本文中的例子对上述所有网络插件都有效
|
||||
:::
|
||||
|
||||
## 创建一个Deployment并配置Service
|
||||
|
||||
* 创建一个 `nginx` Deployment 用于演示 Kubernetes 的 NetworkPolicy:
|
||||
|
||||
``` sh
|
||||
kubectl create deployment nginx --image=nginx
|
||||
```
|
||||
输出结果
|
||||
```
|
||||
deployment.apps/nginx created
|
||||
```
|
||||
|
||||
* 通过Service暴露该Deployment
|
||||
|
||||
``` sh
|
||||
kubectl expose deployment nginx --port=80
|
||||
```
|
||||
输出结果
|
||||
```
|
||||
service/nginx exposed
|
||||
```
|
||||
|
||||
* 查询结果
|
||||
``` sh
|
||||
kubectl get svc,pod
|
||||
```
|
||||
输出结果
|
||||
```
|
||||
NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE
|
||||
service/kubernetes 10.100.0.1 <none> 443/TCP 46m
|
||||
service/nginx 10.100.0.16 <none> 80/TCP 33s
|
||||
|
||||
NAME READY STATUS RESTARTS AGE
|
||||
pod/nginx-701339712-e0qfq 1/1 Running 0 35s
|
||||
```
|
||||
|
||||
## 从另外一个pod访问Service
|
||||
|
||||
默认是可以从另外一个Pod访问 `nginx` Service 的。下面的方法可以执行此测试:
|
||||
|
||||
在 `default` 名称空间中创建 busybox 容器,并执行 `wget` 命令:
|
||||
|
||||
``` sh
|
||||
kubectl run --generator=run-pod/v1 busybox --rm -ti --image=busybox -- /bin/sh
|
||||
```
|
||||
|
||||
请按照下面的例子,在命令行中执行 `wget --spider --timeout=1 nginx`
|
||||
```
|
||||
Waiting for pod default/busybox-472357175-y0m47 to be running, status is Pending, pod ready: false
|
||||
|
||||
Hit enter for command prompt
|
||||
|
||||
/ # wget --spider --timeout=1 nginx
|
||||
Connecting to nginx (10.100.0.16:80)
|
||||
/ #
|
||||
```
|
||||
|
||||
## 限制对nginx的访问
|
||||
|
||||
下面的 `NetworkPolicy` 可以声明:只有带 `access=true` 标签的 Pod 可以访问 `nginx` 服务:
|
||||
|
||||
<<< @/.vuepress/public/statics/learning/svc/network-policy.yaml
|
||||
|
||||
* 执行命令以创建该 NetworkPolicy:
|
||||
``` sh
|
||||
kubectl apply -f https://kuboard.cn/statics/learning/svc/network-policy.yaml
|
||||
```
|
||||
输出结果如下:
|
||||
```
|
||||
networkpolicy.networking.k8s.io/access-nginx created
|
||||
```
|
||||
|
||||
## 从不带标签的Pod访问nginx服务
|
||||
|
||||
如果从不带标签的 Pod 访问该 nginx 服务,请求将超时:
|
||||
``` sh
|
||||
kubectl run --generator=run-pod/v1 busybox --rm -ti --image=busybox -- /bin/sh
|
||||
```
|
||||
请按照下面的例子在命令行中执行 `wget --spider --timeout=1 nginx`
|
||||
```
|
||||
Waiting for pod default/busybox-472357175-y0m47 to be running, status is Pending, pod ready: false
|
||||
|
||||
Hit enter for command prompt
|
||||
|
||||
/ # wget --spider --timeout=1 nginx
|
||||
Connecting to nginx (10.100.0.16:80)
|
||||
wget: download timed out
|
||||
/ #
|
||||
```
|
||||
|
||||
## 从带有标签的Pod访问nginx服务
|
||||
|
||||
从带有 `access=true` 标签的 Pod 中访问 nginx 服务,将能够执行成功:
|
||||
``` sh
|
||||
kubectl run --generator=run-pod/v1 busybox --rm -ti --labels="access=true" --image=busybox -- /bin/sh
|
||||
```
|
||||
请按照下面的例子在命令行中执行 `wget --spider --timeout=1 nginx`
|
||||
```
|
||||
Waiting for pod default/busybox-472357175-y0m47 to be running, status is Pending, pod ready: false
|
||||
|
||||
Hit enter for command prompt
|
||||
|
||||
/ # wget --spider --timeout=1 nginx
|
||||
Connecting to nginx (10.100.0.16:80)
|
||||
/ #
|
||||
```
|
||||
@ -1,10 +1,10 @@
|
||||
---
|
||||
vssueId: 158
|
||||
layout: LearningLayout
|
||||
description: Kubernetes中_网络策略定义了一组Pod是否允许相互通信_或者与网络中的其他端点endpoint通信
|
||||
description: Kubernetes中_网络策略定义了一组Pod是否允许相互通信_或者与网络中的其他端点endpoint通信_NetworkPolicy对象使用标签选择Pod_并定义规则指定选中的Pod可以执行什么样的网络通信
|
||||
meta:
|
||||
- name: keywords
|
||||
content: Kubernetes教程,K8S教程,Kubernetes服务发现
|
||||
content: Kubernetes教程,K8S教程,Kubernetes Network Policies, K8S 网络策略
|
||||
---
|
||||
|
||||
# Network Policies
|
||||
|
||||
Reference in New Issue
Block a user