来源: 容器编排系统k8s之Ingress资源 – Linux-1874 – 博客园
前文我们了解了k8s上的service资源的相关话题,回顾请参考:https://www.cnblogs.com/qiuhom-1874/p/14161950.html;今天我们来了解下k8s上的Ingress资源的相关话题;
我们知道在k8s上service是用来解决Pod访问问题,它是通过kube-proxy在每个节点上创建iptables规则或ipvs规则,在用户请求某个pod时,用户的请求会被其service规则所捕获,从而实现访问对应pod;对于service来讲,用户请求直接在传输层就被捕获转发,效率很高效,但这同时也引入了一个新问题;比如我们运行的pod对外客户端访问需要https通信,如果使用service这种4层调度,那就意味着每个pod上我们要配置证书,这很显然不是我们想要做的;那有没有什么办法做到在用户访问pod对应的service时使用https,而对应pod里又不用https协议呢?答案是有的;比如我们可以使用nginx来做https会话卸载器;我们只需要在代理上配置证书即可;又比如我们在k8s上运行了各种各样的pod,这些pod的功能每个都不一样,有点是专门处理用户认证的,有点是专门处理站点主页的,有点专门处理支付的等等,而这些pod对外都是提供一个独有的url,那么这些pod需要怎么才能被集群外部访问到呢?我们知道对于一个站点来讲,如果后端有多个server同时提供一种服务,我们可以把这些同功能的server定义成一个组,然后使用nginx代理将不同功能url的访问代理到不同组上即可;这样一来解决了后端多server被负载访问的问题;那么对于k8s上这种同功能的pod怎么归并成一个组呢?用户访问不同url怎么调度到不同的组上呢?很显然要想实现这些功能,在k8s上应该有一个类似nginx一样的代理存在;这个代理就叫做ingress 控制器;ingress 控制器和k8s上的其他控制不一样,ingress控制器并不能直接运行为kube-controller-manager的一部分,它类似k8s集群上的coredns,需要在集群上单独部署,本质上就是一个pod,我们可以使用k8s上的ds或deploy控制器来创建它;ingress controller pod的作用主要是引入集群外部流量,并实时监控着apiserver上ingress资源的变动,并将其ingress中定义的规则转化为对应ingress控制器对应应用程序的专有配置,然后动态的重载或重启对应守护进程来使其配置文件生效;在k8s上ingress是一种标准资源,它本质上就是我们定义的基于dns名称(host)或url路径把请求转发至指定service资源的规则;简单讲ingress就是我们用来定义代理的配置所创建的资源;ingress控制器就是把对应ingress规则转换为对应ingress控制器中应用程序的专有配置,然后重启或重载对应配置文件使其生效的组件;
ingress和ingress controller pod的关系
提示:如上图所示,ingress就是ingress 控制器pod的代理规则;用户请求某个后端pod所提供的服务时,首先会通过ingress controller pod把流量引入到集群内部,然后ingress controller pod根据ingress定义的规则,把对应ingress规则转化为对应ingress controller pod实现的对应应用的配置(ingress controller 可以由任何具有七层反向代理功能的服务实现,比如nginx,haproxy等等)然后再适配用户请求,把对应请求反代到对应service上;而对于pod的选择上,ingress控制器可以基于对应service中的标签选择器,直接同pod直接通信,无须通过service对象api的再次转发,从而省去了用户请求到kube-proxy实现的代理开销(本质上ingress controller 也是运行为一个pod,和其他pod在同一网段中);
ingress controller部署
在k8s上ingress controller的实现有很多,比如基于nginx的,基于haproxy的等等,这里以nginx为例;
下载ingress-nginx包
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wget https://github.com/kubernetes/ingress-nginx/archive/nginx-0.28.0.tar.gz |
解压包,找到对应的部署清单
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[root@master01 ~]# lltotal 92144-rw------- 1 root root 65586688 Dec 8 15:16 flannel-v0.13.1-rc1.tardrwxr-xr-x 2 root root 4096 Dec 21 21:04 manifests-rw-r--r-- 1 root root 28760559 Dec 21 21:02 nginx-0.28.0.tar.gz[root@master01 ~]# tar xf nginx-0.28.0.tar.gz[root@master01 ~]# lsflannel-v0.13.1-rc1.tar ingress-nginx-nginx-0.28.0 manifests nginx-0.28.0.tar.gz[root@master01 ~]# cd ingress-nginx-nginx-0.28.0/[root@master01 ingress-nginx-nginx-0.28.0]# lsbuild code-of-conduct.md docs hack labels.yaml mkdocs.yml README.md SECURITY_CONTACTS versionChangelog.md CONTRIBUTING.md go.mod images LICENSE OWNERS requirements-docs.txt testcmd deploy go.sum internal Makefile OWNERS_ALIASES rootfs vendor[root@master01 ingress-nginx-nginx-0.28.0]# cd deploy/[root@master01 deploy]# lsaws cloud-generic grafana prometheus static with-validating-webhook.yaml.tplbaremetal cluster-wide minikube README.md validating-webhook.yaml.tpl[root@master01 deploy]# cd static/[root@master01 static]# lsconfigmap.yaml mandatory.yaml namespace.yaml provider rbac.yaml with-rbac.yaml[root@master01 static]# pwd/root/ingress-nginx-nginx-0.28.0/deploy/static[root@master01 static]# |
提示:资源配置清单在ingress-nginx-nginx-0.28.0/deploy/static下,名为mandatory.yaml;
资源配置清单内容
apiVersion: v1
kind: Namespace
metadata:
name: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: nginx-configuration
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: tcp-services
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: udp-services
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
name: nginx-ingress-clusterrole
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- configmaps
- endpoints
- nodes
- pods
- secrets
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes
verbs:
- get
- apiGroups:
- ""
resources:
- services
verbs:
- get
- list
- watch
- apiGroups:
- ""
resources:
- events
verbs:
- create
- patch
- apiGroups:
- "extensions"
- "networking.k8s.io"
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- "extensions"
- "networking.k8s.io"
resources:
- ingresses/status
verbs:
- update
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: Role
metadata:
name: nginx-ingress-role
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- configmaps
- pods
- secrets
- namespaces
verbs:
- get
- apiGroups:
- ""
resources:
- configmaps
resourceNames:
# Defaults to "<election-id>-<ingress-class>"
# Here: "<ingress-controller-leader>-<nginx>"
# This has to be adapted if you change either parameter
# when launching the nginx-ingress-controller.
- "ingress-controller-leader-nginx"
verbs:
- get
- update
- apiGroups:
- ""
resources:
- configmaps
verbs:
- create
- apiGroups:
- ""
resources:
- endpoints
verbs:
- get
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
name: nginx-ingress-role-nisa-binding
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: nginx-ingress-role
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: nginx-ingress-clusterrole-nisa-binding
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: nginx-ingress-clusterrole
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-ingress-controller
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
spec:
replicas: 1
selector:
matchLabels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
template:
metadata:
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
annotations:
prometheus.io/port: "10254"
prometheus.io/scrape: "true"
spec:
# wait up to five minutes for the drain of connections
terminationGracePeriodSeconds: 300
serviceAccountName: nginx-ingress-serviceaccount
nodeSelector:
kubernetes.io/os: linux
containers:
- name: nginx-ingress-controller
image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.28.0
args:
- /nginx-ingress-controller
- --configmap=$(POD_NAMESPACE)/nginx-configuration
- --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
- --udp-services-configmap=$(POD_NAMESPACE)/udp-services
- --publish-service=$(POD_NAMESPACE)/ingress-nginx
- --annotations-prefix=nginx.ingress.kubernetes.io
securityContext:
allowPrivilegeEscalation: true
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
# www-data -> 101
runAsUser: 101
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
ports:
- name: http
containerPort: 80
protocol: TCP
- name: https
containerPort: 443
protocol: TCP
livenessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 10
readinessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 10
lifecycle:
preStop:
exec:
command:
- /wait-shutdown
---
apiVersion: v1
kind: LimitRange
metadata:
name: ingress-nginx
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
spec:
limits:
- default:
min:
memory: 90Mi
cpu: 100m
type: Container
提示:以上清单主要定义了一个名称ingress-nginx的名称空间,在其名称空间下创建了几个configmap,最重要的是用deployment创建了一个ingress-nginx pod;
这里说一下,对于ingress-nginx控制器,它本质还是运行为一个pod,对于pod来说要想接入外部访问流量到集群内部来,有三种方式,一种是使用NodePort类型的service;第二种是使用ds或deploy控制器,在定义pod模板时使用hostPort把pod端口映射到宿主机方式;第三种是定义pod模板时使用hostNetwork,直接共享宿主机网络名称空间;如下所示
使用专有NodePort service来引入外部流量
提示:这种使用deploy控制管理ingress controller pod,如果在pod模板中没有暴露端口,则需要创建一个service资源来暴露ingress controller pod的端口来引入外部流量到集群内部;
使用ds控制器管理ingress controller pod在pod模板中使用hostPort方式暴露端口
提示:使用ds控制器能够保证每个节点上只运行一个ingress controller,所以我们可以把对应ingress controller pod端端口通过端口映射的方式映射到宿主机上的某一固定端口;
使用ds控制器在pod模板中使用hostNetwork方式共享宿主机网络名称空间
提示:共享宿主机网络名称空间,也必须使用ds控制器来确保对应每个节点上只能运行一个ingress controller pod,这样才能确保每个ingress controller pod能够正常把端口暴露出去,以供集群外部客户端访问;
选择上述其中一种方式暴露ingress controller pod的端口即可;如果选择使用ds控制器来暴露端口,我们就需要修改其对应资源配置清单中的pod模板,如下所示
使用ds控制器来管理ingress controller pod在pod模板中使用hostPort方式暴露端口
apiVersion: v1
kind: Namespace
metadata:
name: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: nginx-configuration
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: tcp-services
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: udp-services
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
name: nginx-ingress-clusterrole
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- configmaps
- endpoints
- nodes
- pods
- secrets
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes
verbs:
- get
- apiGroups:
- ""
resources:
- services
verbs:
- get
- list
- watch
- apiGroups:
- ""
resources:
- events
verbs:
- create
- patch
- apiGroups:
- "extensions"
- "networking.k8s.io"
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- "extensions"
- "networking.k8s.io"
resources:
- ingresses/status
verbs:
- update
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: Role
metadata:
name: nginx-ingress-role
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- configmaps
- pods
- secrets
- namespaces
verbs:
- get
- apiGroups:
- ""
resources:
- configmaps
resourceNames:
# Defaults to "<election-id>-<ingress-class>"
# Here: "<ingress-controller-leader>-<nginx>"
# This has to be adapted if you change either parameter
# when launching the nginx-ingress-controller.
- "ingress-controller-leader-nginx"
verbs:
- get
- update
- apiGroups:
- ""
resources:
- configmaps
verbs:
- create
- apiGroups:
- ""
resources:
- endpoints
verbs:
- get
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
name: nginx-ingress-role-nisa-binding
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: nginx-ingress-role
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: nginx-ingress-clusterrole-nisa-binding
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: nginx-ingress-clusterrole
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: nginx-ingress-controller
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
spec:
selector:
matchLabels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
template:
metadata:
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
annotations:
prometheus.io/port: "10254"
prometheus.io/scrape: "true"
spec:
# wait up to five minutes for the drain of connections
terminationGracePeriodSeconds: 300
serviceAccountName: nginx-ingress-serviceaccount
nodeSelector:
kubernetes.io/os: linux
containers:
- name: nginx-ingress-controller
image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.28.0
args:
- /nginx-ingress-controller
- --configmap=$(POD_NAMESPACE)/nginx-configuration
- --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
- --udp-services-configmap=$(POD_NAMESPACE)/udp-services
- --publish-service=$(POD_NAMESPACE)/ingress-nginx
- --annotations-prefix=nginx.ingress.kubernetes.io
securityContext:
allowPrivilegeEscalation: true
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
# www-data -> 101
runAsUser: 101
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
ports:
- name: http
containerPort: 80
hostPort: 30080
protocol: TCP
- name: https
containerPort: 443
hostPort: 30443
protocol: TCP
livenessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 10
readinessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 10
lifecycle:
preStop:
exec:
command:
- /wait-shutdown
---
apiVersion: v1
kind: LimitRange
metadata:
name: ingress-nginx
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
spec:
limits:
- default:
min:
memory: 90Mi
cpu: 100m
type: Container
提示:只需把对应控制器类型更改为DaemonSet,在pod模板中spec字段下把replicas去掉;在spec.template.spec.containers.ports字段中加上nodePort字段指定要把容器的端口映射到宿主机上某个端口;如果暴露的端口是非标准端口,在对应k8s集群外部我们还需要部署反代,比如使用nginx,haproxy,lvs;
使用ds控制器管理ingress controller pod在ds控制器资源配置中使用hostNetwork
apiVersion: v1
kind: Namespace
metadata:
name: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: nginx-configuration
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: tcp-services
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
kind: ConfigMap
apiVersion: v1
metadata:
name: udp-services
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
name: nginx-ingress-clusterrole
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- configmaps
- endpoints
- nodes
- pods
- secrets
verbs:
- list
- watch
- apiGroups:
- ""
resources:
- nodes
verbs:
- get
- apiGroups:
- ""
resources:
- services
verbs:
- get
- list
- watch
- apiGroups:
- ""
resources:
- events
verbs:
- create
- patch
- apiGroups:
- "extensions"
- "networking.k8s.io"
resources:
- ingresses
verbs:
- get
- list
- watch
- apiGroups:
- "extensions"
- "networking.k8s.io"
resources:
- ingresses/status
verbs:
- update
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: Role
metadata:
name: nginx-ingress-role
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
rules:
- apiGroups:
- ""
resources:
- configmaps
- pods
- secrets
- namespaces
verbs:
- get
- apiGroups:
- ""
resources:
- configmaps
resourceNames:
# Defaults to "<election-id>-<ingress-class>"
# Here: "<ingress-controller-leader>-<nginx>"
# This has to be adapted if you change either parameter
# when launching the nginx-ingress-controller.
- "ingress-controller-leader-nginx"
verbs:
- get
- update
- apiGroups:
- ""
resources:
- configmaps
verbs:
- create
- apiGroups:
- ""
resources:
- endpoints
verbs:
- get
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: RoleBinding
metadata:
name: nginx-ingress-role-nisa-binding
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: nginx-ingress-role
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRoleBinding
metadata:
name: nginx-ingress-clusterrole-nisa-binding
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: nginx-ingress-clusterrole
subjects:
- kind: ServiceAccount
name: nginx-ingress-serviceaccount
namespace: ingress-nginx
---
apiVersion: apps/v1
kind: DaemonSet
metadata:
name: nginx-ingress-controller
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
spec:
selector:
matchLabels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
template:
metadata:
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
annotations:
prometheus.io/port: "10254"
prometheus.io/scrape: "true"
spec:
# wait up to five minutes for the drain of connections
terminationGracePeriodSeconds: 300
serviceAccountName: nginx-ingress-serviceaccount
nodeSelector:
kubernetes.io/os: linux
hostNetwork: true
containers:
- name: nginx-ingress-controller
image: quay.io/kubernetes-ingress-controller/nginx-ingress-controller:0.28.0
args:
- /nginx-ingress-controller
- --configmap=$(POD_NAMESPACE)/nginx-configuration
- --tcp-services-configmap=$(POD_NAMESPACE)/tcp-services
- --udp-services-configmap=$(POD_NAMESPACE)/udp-services
- --publish-service=$(POD_NAMESPACE)/ingress-nginx
- --annotations-prefix=nginx.ingress.kubernetes.io
securityContext:
allowPrivilegeEscalation: true
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
# www-data -> 101
runAsUser: 101
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
ports:
- name: http
containerPort: 80
protocol: TCP
- name: https
containerPort: 443
protocol: TCP
livenessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
initialDelaySeconds: 10
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 10
readinessProbe:
failureThreshold: 3
httpGet:
path: /healthz
port: 10254
scheme: HTTP
periodSeconds: 10
successThreshold: 1
timeoutSeconds: 10
lifecycle:
preStop:
exec:
command:
- /wait-shutdown
---
apiVersion: v1
kind: LimitRange
metadata:
name: ingress-nginx
namespace: ingress-nginx
labels:
app.kubernetes.io/name: ingress-nginx
app.kubernetes.io/part-of: ingress-nginx
spec:
limits:
- default:
min:
memory: 90Mi
cpu: 100m
type: Container
提示:把对应控制器类型更改外DaemonSet,在pod模板中spec字段下的replicas字段去掉;在spec.template.spec字段下加上hostNetwork: true即可;以上两种使用ds控制器管理ingress controller pod也可以使用node选择器,来筛选在某个节点上创建ingress controller pod;
使用deploy控制器管理ingress controller pod,就直接应用mandatory.yaml即可
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[root@master01 ~]# kubectl apply -f mandatory.yamlnamespace/ingress-nginx createdconfigmap/nginx-configuration createdconfigmap/tcp-services createdconfigmap/udp-services createdserviceaccount/nginx-ingress-serviceaccount createdWarning: rbac.authorization.k8s.io/v1beta1 ClusterRole is deprecated in v1.17+, unavailable in v1.22+; use rbac.authorization.k8s.io/v1 ClusterRoleclusterrole.rbac.authorization.k8s.io/nginx-ingress-clusterrole createdWarning: rbac.authorization.k8s.io/v1beta1 Role is deprecated in v1.17+, unavailable in v1.22+; use rbac.authorization.k8s.io/v1 Rolerole.rbac.authorization.k8s.io/nginx-ingress-role createdWarning: rbac.authorization.k8s.io/v1beta1 RoleBinding is deprecated in v1.17+, unavailable in v1.22+; use rbac.authorization.k8s.io/v1 RoleBindingrolebinding.rbac.authorization.k8s.io/nginx-ingress-role-nisa-binding createdWarning: rbac.authorization.k8s.io/v1beta1 ClusterRoleBinding is deprecated in v1.17+, unavailable in v1.22+; use rbac.authorization.k8s.io/v1 ClusterRoleBindingclusterrolebinding.rbac.authorization.k8s.io/nginx-ingress-clusterrole-nisa-binding createddeployment.apps/nginx-ingress-controller createdlimitrange/ingress-nginx created[root@master01 ~]# |
查看应用资源清单创建的资源对象
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[root@master01 ~]# kubectl get all -n ingress-nginxNAME READY STATUS RESTARTS AGEpod/nginx-ingress-controller-5466cb8999-4lsjc 1/1 Running 0 80sNAME READY UP-TO-DATE AVAILABLE AGEdeployment.apps/nginx-ingress-controller 1/1 1 1 80sNAME DESIRED CURRENT READY AGEreplicaset.apps/nginx-ingress-controller-5466cb8999 1 1 1 80s[root@master01 ~]# |
提示:可以看到在ingress-nginx名称空间下创建了一个deploy控制器,对应控制器创建了一个nginx-ingress-controller控制器pod;但是此pod现在不能被外部客户端访问到,我们需要创建一个service来引入外部流量到此pod上;
查看pod标签
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[root@master01 ~]# kubectl get pod -n ingress-nginx --show-labelsNAME READY STATUS RESTARTS AGE LABELSnginx-ingress-controller-5466cb8999-4lsjc 1/1 Running 0 4m38s app.kubernetes.io/name=ingress-nginx,app.kubernetes.io/part-of=ingress-nginx,pod-template-hash=5466cb8999[root@master01 ~]# |
根据上述标签来写一个创建ingress-service资源的配置清单
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[root@master01 ~]# cat ingress-nginx-service.yamlapiVersion: v1kind: Servicemetadata: name: ingress-nginx-svc namespace: ingress-nginxspec: type: NodePort ports: - port: 80 name: http nodePort: 30080 - port: 443 name: https nodePort: 30443 selector: app.kubernetes.io/name: ingress-nginx app.kubernetes.io/part-of: ingress-nginx[root@master01 ~]# |
提示:以上配置清单主要把满足对应标签选择器的pod关联起来;并把对应pod的80和443端口分别映射到对应主机上的30080和30443端口;
应用配置清单
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[root@master01 ~]# kubectl apply -f ingress-nginx-service.yamlservice/ingress-nginx-svc created[root@master01 ~]# kubectl get svc -n ingress-nginxNAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGEingress-nginx-svc NodePort 10.98.4.208 <none> 80:30080/TCP,443:30443/TCP 13s[root@master01 ~]# |
访问集群任意节点ip的30080和30443端口,看看是否访问到对应pod?
提示:30080是能够正常访问的,只是它显示404,是因为我们没有对应的主页;
访问30443端口
提示:30443是一个https端口,所以访问必须用https协议访问,这里提示访问页面有风险是因为浏览器不信任证书引起的,我们可以点击高级,信任证书即可;同样30443端口也是返回404,是因为没有主页的原因;两个端口能够正常访问,说明我们在k8s上部署的ingress-nginx controller就部署好了;
ingress资源的使用
在k8s上创建一个deploy控制器,让其管理2个 ikubernetes/myapp:v1镜像运行的pod,然后再创建一个对应的service
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[root@master01 manifests]# cat myapp-demo.yamlapiVersion: apps/v1kind: Deploymentmetadata: name: myapp namespace: defaultspec: replicas: 2 selector: matchLabels: app: myapp rel: stable template: metadata: namespace: default labels: app: myapp rel: stable spec: containers: - name: myapp image: ikubernetes/myapp:v1---apiVersion: v1kind: Servicemetadata: name: myapp namespace: defaultspec: selector: app: myapp rel: stable ports: - name: http port: 80 targetPort: 80[root@master01 manifests]# |
提示:一个清单中定义多个资源,需要用“—”来分割资源;
应用资源清单
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[root@master01 manifests]# kubectl apply -f myapp-demo.yamldeployment.apps/myapp createdservice/myapp created[root@master01 manifests]# kubectl get pod -o wideNAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATESmyapp-6479b786f5-9d4mh 1/1 Running 0 11s 10.244.2.98 node02.k8s.org <none> <none>myapp-6479b786f5-k252c 1/1 Running 0 11s 10.244.4.20 node04.k8s.org <none> <none>[root@master01 manifests]# kubectl get svcNAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGEkubernetes ClusterIP 10.96.0.1 <none> 443/TCP 4h52mmyapp ClusterIP 10.105.208.218 <none> 80/TCP 21s[root@master01 manifests]# kubectl describe svc myappName: myappNamespace: defaultLabels: <none>Annotations: <none>Selector: app=myapp,rel=stableType: ClusterIPIP Families: <none>IP: 10.105.208.218IPs: 10.105.208.218Port: http 80/TCPTargetPort: 80/TCPEndpoints: 10.244.2.98:80,10.244.4.20:80Session Affinity: NoneEvents: <none>[root@master01 manifests]# |
创建ingress资源来反代以上资源
示例:创建ingress资源
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[root@master01 manifests]# cat ingress-myapp.yamlapiVersion: extensions/v1beta1kind: Ingressmetadata: name: ingress-myapp namespace: default annotations: kubernetes.io/ingress.class: "nginx"spec: rules: - host: www.myapp.com http: paths: - path: / backend: serviceName: myapp servicePort: 80[root@master01 manifests]# |
提示:创建ingress资源apiVersion的值要写成extensions/v1beta1,kind为Ingress;对应metadata中的annotations的配置表示把ingress资源通知给那个类别的ingress controller,如果k8s集群上有多个类别的ingress controller时,这一项特别有用;在spec字段主要内嵌了三个字段,rules字段用来定义反代规则列表,其值为一个对象列表;其中rules字段里主要host和http字段;host用来指定虚拟主机的fqdn名称,如果不写表示匹配任意虚拟主机名称;http是用来定义指向后端的http选择器列表;其值为一个对象,里面只有一个paths字段,用于指定把请求映射到后端的某个路径;其值为一个对象列表;对应paths字段中可以定义path,用来指定映射后端的路径;backend用于指定后端pod的service,其值为一个对象;serviceName用于指定对应pod的service名称;servicePort用于指定后端服务的端口;以上配置表示把www.myapp.com这个虚拟主机的访问全部反代至服务名称为myapp端口为80的pod上;
应用配置清单
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[root@master01 manifests]# kubectl apply -f ingress-myapp.yamlWarning: extensions/v1beta1 Ingress is deprecated in v1.14+, unavailable in v1.22+; use networking.k8s.io/v1 Ingressingress.extensions/ingress-myapp created[root@master01 manifests]# kubectl get ingressNAME CLASS HOSTS ADDRESS PORTS AGEingress-myapp <none> www.myapp.com 80 29s[root@master01 manifests]# |
查看ingress资源的详细信息
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[root@master01 manifests]# kubectl describe ingress ingress-myappName: ingress-myappNamespace: defaultAddress: Default backend: default-http-backend:80 (<error: endpoints "default-http-backend" not found>)Rules: Host Path Backends ---- ---- -------- www.myapp.com / myapp:80 (10.244.2.98:80,10.244.4.20:80)Annotations: kubernetes.io/ingress.class: nginxEvents: Type Reason Age From Message ---- ------ ---- ---- ------- Normal CREATE 81s nginx-ingress-controller Ingress default/ingress-myapp[root@master01 manifests]# |
提示:可以看到对应满足service名称为myapp并且其端口为80的pod有两个;
进入ingress controller pod里,看看对应配置文件是否有www.myapp.com的配置?
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[root@master01 manifests]# kubectl get pods -n ingress-nginxNAME READY STATUS RESTARTS AGEnginx-ingress-controller-5466cb8999-4lsjc 1/1 Running 0 78m[root@master01 manifests]# kubectl exec -it -n ingress-nginx pod/nginx-ingress-controller-5466cb8999-4lsjc -- /bin/sh/etc/nginx $ cd /etc/nginx//etc/nginx $ lsfastcgi.conf koi-utf modsecurity owasp-modsecurity-crs uwsgi_params.defaultfastcgi.conf.default koi-win modules scgi_params win-utffastcgi_params lua nginx.conf scgi_params.defaultfastcgi_params.default mime.types nginx.conf.default templategeoip mime.types.default opentracing.json uwsgi_params/etc/nginx $ grep "www.myapp.com" nginx.conf ## start server www.myapp.com server_name www.myapp.com ; ## end server www.myapp.com/etc/nginx $ |
提示:可以看到在对应ingress-nginx 控制器pod中能够搜索到www.myapp.com的配置;说明我们定义的ingress资源已经被ingress-nginx controller 捕获;
用浏览器访问www.myapp.com看看是否能够访问到内容?
提示:使用www.myapp.com访问,需要确保对应域名能够正常解析到k8s集群任意一节点上;可以看到访问www.myapp.com:30080能够访问到对应pod内容;
删除ingress代理规则
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[root@master01 manifests]# kubectl delete -f ingress-myapp.yamlWarning: extensions/v1beta1 Ingress is deprecated in v1.14+, unavailable in v1.22+; use networking.k8s.io/v1 Ingressingress.extensions "ingress-myapp" deleted[root@master01 manifests]# kubectl get ingressNo resources found in default namespace.[root@master01 manifests]# |
示例:配置基于url路径进行流量分发
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[root@master01 manifests]# cat ingress-myapp1.yamlapiVersion: extensions/v1beta1kind: Ingressmetadata: name: ingress-myapp namespace: default annotations: kubernetes.io/ingress.class: "nginx" ingress.kubernetes.io/rewrite-target: /spec: rules: - host: www.myapp.com http: paths: - path: /bbs backend: serviceName: myapp servicePort: 80 - path: /blog backend: serviceName: myapp servicePort: 80[root@master01 manifests]# |
提示:以上配置表示把www.myapp.com/bbs反代到service名称为myapp并且端口为80的pod上;把www.myapp.com/blog反代到ervice名称为myapp并且端口为80的pod上;我这里是因为k8s上只有这一种应用,生成环境中按照对应的业务逻辑来反代对应url到对应pod上即可;
应用配置清单
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[root@master01 manifests]# kubectl apply -f ingress-myapp1.yamlWarning: extensions/v1beta1 Ingress is deprecated in v1.14+, unavailable in v1.22+; use networking.k8s.io/v1 Ingressingress.extensions/ingress-myapp created[root@master01 manifests]# kubectl get ingressNAME CLASS HOSTS ADDRESS PORTS AGEingress-myapp <none> www.myapp.com 80 5s[root@master01 manifests]# kubectl describe ingress ingress-myappName: ingress-myappNamespace: defaultAddress: Default backend: default-http-backend:80 (<error: endpoints "default-http-backend" not found>)Rules: Host Path Backends ---- ---- -------- www.myapp.com /bbs myapp:80 (10.244.2.98:80,10.244.4.20:80) /blog myapp:80 (10.244.2.98:80,10.244.4.20:80)Annotations: ingress.kubernetes.io/rewrite-target: / kubernetes.io/ingress.class: nginxEvents: Type Reason Age From Message ---- ------ ---- ---- ------- Normal CREATE 30s nginx-ingress-controller Ingress default/ingress-myapp[root@master01 manifests]# |
提示:可以看到对应ingress上就有两个url分别指向后端service名称为myapp端口为80的pod上;
访问对应url,看看是否访问到内容?
提示:这里访问不到内容的原因是对应pod内部并没有对应url的页面;
进入ingress controller pod内部,查看是否有对应配置?
提示:可以看到对应在ingress中定义的配置,都转为对应该ingress controller pod中的配置,说明我们定义基于url分发流量的ingress没有问题;
示例:定义ingress规则基于主机名称的虚拟主机
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[root@master01 manifests]# cat ingress-myapp2.yamlapiVersion: extensions/v1beta1kind: Ingressmetadata: name: ingress-myapp namespace: default annotations: kubernetes.io/ingress.class: "nginx" ingress.kubernetes.io/rewrite-target: /spec: rules: - host: www.myapp.com http: paths: - path: backend: serviceName: myapp servicePort: 80 - host: blog.myapp.com http: paths: - path: backend: serviceName: myapp servicePort: 80[root@master01 manifests]# |
提示:以上配置表示把www.myapp.com这个虚拟主机名称的访问流量分发至service名称为myapp端口为80的pod上;把blog.myapp.com的流量分发至至service名称为myapp端口为80的pod上;生成环境按照对应的service名称来分发即可;
应用配置清单
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[root@master01 manifests]# kubectl apply -f ingress-myapp2.yamlWarning: extensions/v1beta1 Ingress is deprecated in v1.14+, unavailable in v1.22+; use networking.k8s.io/v1 Ingressingress.extensions/ingress-myapp created[root@master01 manifests]# kubectl get ingressNAME CLASS HOSTS ADDRESS PORTS AGEingress-myapp <none> www.myapp.com,blog.myapp.com 80 16s[root@master01 manifests]# kubectl describe ingress ingress-myappName: ingress-myappNamespace: defaultAddress: Default backend: default-http-backend:80 (<error: endpoints "default-http-backend" not found>)Rules: Host Path Backends ---- ---- -------- www.myapp.com myapp:80 (10.244.2.98:80,10.244.4.20:80) blog.myapp.com myapp:80 (10.244.2.98:80,10.244.4.20:80)Annotations: ingress.kubernetes.io/rewrite-target: / kubernetes.io/ingress.class: nginxEvents: Type Reason Age From Message ---- ------ ---- ---- ------- Normal CREATE 32s nginx-ingress-controller Ingress default/ingress-myapp[root@master01 manifests]# |
验证配置信息
访问对应虚拟主机,看看是否能够访问对应pod?
提示:可以看到两个虚拟主机名称都可以正常访问到,对应也做了调度;
示例:创建tls类型的ingress资源
创建证书
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[root@master01 manifests]# openssl genrsa -out tls.key 2048Generating RSA private key, 2048 bit long modulus.........................................+++........+++e is 65537 (0x10001)[root@master01 manifests]# openssl req -x509 -key tls.key -out tls.crt -subj /C=CN/ST=SiChuan/L=GuangYuan/O=Test/CN=www.myapp.com -days 3650 [root@master01 manifests]# |
提示:以上两条命令创建了一个名为tls.key的私钥和一个自签名证书,其名为tls.crt;
创建Secret资源
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[root@master01 manifests]# kubectl create secret tls www-myapp-com-ingress-secret --cert=./tls.crt --key=./tls.keysecret/www-myapp-com-ingress-secret created[root@master01 manifests]# kubectl get secretNAME TYPE DATA AGEdefault-token-xvd4c kubernetes.io/service-account-token 3 13dwww-myapp-com-ingress-secret kubernetes.io/tls 2 21s[root@master01 manifests]# |
提示:在ingress控制器上配置https主机时,不能直接使用私钥和证书文件,而是需要使用secret资源对象来传递相关数据;
定义tls类型ingress资源清单
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[root@master01 manifests]# cat www-myapp-com-ingress-secret.yamlapiVersion: extensions/v1beta1kind: Ingressmetadata: name: ingress-myapp-tls namespace: default annotations: kubernetes.io/ingress.class: "nginx"spec: tls: - hosts: - www.myapp.com secretName: www-myapp-com-ingress-secret rules: - host: www.myapp.com http: paths: - path: / backend: serviceName: myapp servicePort: 80[root@master01 manifests]# |
提示:定义tls类型ingress资源清单,需要在spec字段下用tls字段来指定对应主机名称,以及secret资源对象的名称;
应用资源清单
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[root@master01 manifests]# kubectl apply -f www-myapp-com-ingress-secret.yamlWarning: extensions/v1beta1 Ingress is deprecated in v1.14+, unavailable in v1.22+; use networking.k8s.io/v1 Ingressingress.extensions/ingress-myapp-tls created[root@master01 manifests]# kubectl get ingressNAME CLASS HOSTS ADDRESS PORTS AGEingress-myapp <none> www.myapp.com,blog.myapp.com 80 31mingress-myapp-tls <none> www.myapp.com 80, 443 8s[root@master01 manifests]# kubectl describe ingress ingress-myapp-tlsName: ingress-myapp-tlsNamespace: defaultAddress: Default backend: default-http-backend:80 (<error: endpoints "default-http-backend" not found>)TLS: www-myapp-com-ingress-secret terminates www.myapp.comRules: Host Path Backends ---- ---- -------- www.myapp.com / myapp:80 (10.244.2.98:80,10.244.4.20:80)Annotations: kubernetes.io/ingress.class: nginxEvents: Type Reason Age From Message ---- ------ ---- ---- ------- Normal CREATE 26s nginx-ingress-controller Ingress default/ingress-myapp-tls[root@master01 manifests]# |
验证:访问对应虚拟主机名称,看看对应的https端口是否能够正常访问到内容?
提示:可以看到使用https协议访问对应的30443端口能够正常访问到对应后端pod提供的内容;
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