kubernetes二： kubernetes 重要组件安装和集群管理
一、管理k8s资源
1.管理k8s核心资源的三种基本方法
- 陈述式管理方法----主要依赖命令行cli工具进行管理
- 声明式管理方法--主要依赖统一资源配置清单（manifest）进行管理
- GUI式管理方法--主要依赖图形化操作界面（web页面）进行管理
2.陈述式管理方法
2.1 管理namespace资源
##查看名称空间
[root@kjdow7-21 ~]# kubectl get namespaces #或者 kubectl get ns
NAME STATUS AGE
default Active 4d18h
kube-node-lease Active 4d18h
kube-public Active 4d18h
kube-system Active 4d18h
##查看名称空间内的资源
[root@kjdow7-21 ~]# kubectl get all -n default
NAME READY STATUS RESTARTS AGE
pod/nginx-ds-ssdtm 1/1 Running 1 2d18h
pod/nginx-ds-xfsk4 1/1 Running 1 2d18h
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 192.168.0.1 <none> 443/TCP 4d19h
NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE
daemonset.apps/nginx-ds 2 2 2 2 2 <none> 2d18h
##创建名称空间
[root@kjdow7-21 ~]# kubectl create namespace app
namespace/app created
##删除名称空间
[root@kjdow7-21 ~]# kubectl delete namespace app
namespace "app" deleted
注意： namespace可以简写为ns；
2.2 管理Deploymen资源
##创建deployment
[root@kjdow7-21 ~]# kubectl create deployment nginx-dp --image=harbor.phc-dow.com/public/nginx:v1.7.9 -n kube-public
deployment.apps/nginx-dp created
[root@kjdow7-21 ~]# kubectl get all -n kube-public
NAME READY STATUS RESTARTS AGE
pod/nginx-dp-67f6684bb9-zptmd 1/1 Running 0 26s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/nginx-dp 1/1 1 1 27s
NAME DESIRED CURRENT READY AGE
replicaset.apps/nginx-dp-67f6684bb9 1 1 1 26s
###查看deployment资源
[root@kjdow7-21 ~]# kubectl get deployment -n kube-public
NAME READY UP-TO-DATE AVAILABLE AGE
nginx-dp 1/1 1 1 42m
注意： deployment可以简写为deploy
###长格式显示deployment信息
[root@kjdow7-21 ~]# kubectl get deploy -n kube-public -o wide
NAME READY UP-TO-DATE AVAILABLE AGE CONTAINERS IMAGES SELECTOR
nginx-dp 1/1 1 1 53m nginx harbor.phc-dow.com/public/nginx:v1.7.9 app=nginx-dp
###查看deployment详细信息
[root@kjdow7-21 ~]# kubectl describe deployment nginx-dp -n kube-public
Name: nginx-dp
Namespace: kube-public
CreationTimestamp: Mon, 13 Jan 2020 23:33:45 +0800
Labels: app=nginx-dp
Annotations: deployment.kubernetes.io/revision: 1
Selector: app=nginx-dp
Replicas: 1 desired | 1 updated | 1 total | 1 available | 0 unavailable
StrategyType: RollingUpdate
MinReadySeconds: 0
RollingUpdateStrategy: 25% max unavailable, 25% max surge
Pod Template:
Labels: app=nginx-dp
Containers:
nginx:
Image: harbor.phc-dow.com/public/nginx:v1.7.9
Port: <none>
Host Port: <none>
Environment: <none>
Mounts: <none>
Volumes: <none>
Conditions:
Type Status Reason
---- ------ ------
Available True MinimumReplicasAvailable
Progressing True NewReplicaSetAvailable
OldReplicaSets: <none>
NewReplicaSet: nginx-dp-67f6684bb9 (1/1 replicas created)
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal ScalingReplicaSet 55m deployment-controller Scaled up replica set nginx-dp-67f6684bb9 to 1
2.3 管理pod资源
###查看pod资源
[root@kjdow7-21 ~]# kubectl get pod -n kube-public
NAME READY STATUS RESTARTS AGE
nginx-dp-67f6684bb9-zptmd 1/1 Running 0 104m
###进入pod资源
[root@kjdow7-21 ~]# kubectl exec -it nginx-dp-67f6684bb9-zptmd /bin/bash -n kube-public
root@nginx-dp-67f6684bb9-zptmd:/# ip add
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
9: eth0@if10: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP
link/ether 02:42:ac:07:16:03 brd ff:ff:ff:ff:ff:ff
inet 172.7.22.3/24 brd 172.7.22.255 scope global eth0
valid_lft forever preferred_lft forever
注意：也可以在对应的宿主机上使用docker exec 进入
2.4 删除资源
2.4.1 删除pod
###删除pod
[root@kjdow7-21 ~]# kubectl get pod -n kube-public
NAME READY STATUS RESTARTS AGE
nginx-dp-67f6684bb9-zptmd 1/1 Running 0 146m
[root@kjdow7-21 ~]# kubectl delete pod nginx-dp-67f6684bb9-zptmd -n kube-public
pod "nginx-dp-67f6684bb9-zptmd" deleted
[root@kjdow7-21 ~]# kubectl get pod -n kube-public
NAME READY STATUS RESTARTS AGE
nginx-dp-67f6684bb9-kn8m9 1/1 Running 0 11s
注：删除pod实际上是重启了一个新的pod，因为pod控制器预期有一个pod，删除了一个，就会再启动一个，让它符合预定的预期。
###强制删除pod
[root@kjdow7-21 ~]# kubectl get pod -n kube-public
NAME READY STATUS RESTARTS AGE
nginx-dp-67f6684bb9-kn8m9 1/1 Running 0 22h
[root@kjdow7-21 ~]# kubectl delete pod nginx-dp-67f6684bb9-kn8m9 -n kube-public --force --grace-period=0
warning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.
pod "nginx-dp-67f6684bb9-kn8m9" force deleted
[root@kjdow7-21 ~]# kubectl get pod -n kube-public
NAME READY STATUS RESTARTS AGE
nginx-dp-67f6684bb9-898p6 1/1 Running 0 17s
--force --grace-period=0 是强制删除
2.4.2 删除deployment
[root@kjdow7-21 ~]# kubectl delete deployment nginx-dp -n kube-public
deployment.extensions "nginx-dp" deleted
[root@kjdow7-21 ~]# kubectl get deployment -n kube-public
No resources found.
[root@kjdow7-21 ~]# kubectl get pod -n kube-public
No resources found.
2.5 service 资源
2.5.1 创建service
###创建service资源
[root@kjdow7-21 ~]# kubectl expose deployment nginx-dp --port=80 -n kube-public
service/nginx-dp exposed
###查看资源
[root@kjdow7-21 ~]# kubectl get all -n kube-public
NAME READY STATUS RESTARTS AGE
pod/nginx-dp-67f6684bb9-l9jqh 1/1 Running 0 13m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/nginx-dp ClusterIP 192.168.208.157 <none> 80/TCP 7m53s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/nginx-dp 1/1 1 1 13m
NAME DESIRED CURRENT READY AGE
replicaset.apps/nginx-dp-67f6684bb9 1 1 1 13m
####service中的cluster-ip就是pod的固定接入点，不管podip怎么变化，cluster-ip不会变
# kubectl get pod -n kube-public -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-dp-67f6684bb9-l9jqh 1/1 Running 0 26m 172.7.22.3 kjdow7-22.host.com <none> <none>
kjdow7-22 ~]# curl 192.168.208.157
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
###可以访问
[root@kjdow7-22 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.0.1:443 nq
-> 10.4.7.21:6443 Masq 1 0 0
-> 10.4.7.22:6443 Masq 1 0 0
TCP 192.168.208.157:80 nq
-> 172.7.22.3:80 Masq 1 0 0
[root@kjdow7-21 ~]# kubectl scale deployment nginx-dp --replicas=2 -n kube-public
deployment.extensions/nginx-dp scaled
[root@kjdow7-22 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.0.1:443 nq
-> 10.4.7.21:6443 Masq 1 0 0
-> 10.4.7.22:6443 Masq 1 0 0
TCP 192.168.208.157:80 nq
-> 172.7.21.3:80 Masq 1 0 0
-> 172.7.22.3:80 Masq 1 0 0
###尝试删除一个pod，查看下状况
[root@kjdow7-21 ~]# kubectl get pod -n kube-public -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-dp-67f6684bb9-l9jqh 1/1 Running 0 39m 172.7.22.3 kjdow7-22.host.com <none> <none>
nginx-dp-67f6684bb9-nn9pq 1/1 Running 0 3m41s 172.7.21.3 kjdow7-21.host.com <none> <none>
[root@kjdow7-21 ~]# kubectl delete pod nginx-dp-67f6684bb9-l9jqh -n kube-public
pod "nginx-dp-67f6684bb9-l9jqh" deleted
[root@kjdow7-21 ~]# kubectl get pod -n kube-public -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-dp-67f6684bb9-lmfvl 1/1 Running 0 9s 172.7.22.4 kjdow7-22.host.com <none> <none>
nginx-dp-67f6684bb9-nn9pq 1/1 Running 0 3m57s 172.7.21.3 kjdow7-21.host.com <none> <none>
[root@kjdow7-21 ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.0.1:443 nq
-> 10.4.7.21:6443 Masq 1 0 0
-> 10.4.7.22:6443 Masq 1 0 0
TCP 192.168.208.157:80 nq
-> 172.7.21.3:80 Masq 1 0 0
-> 172.7.22.4:80 Masq 1 0 0
无论后端的pod的ip如何变化，前面的service的cluster-ip不会变。cluster-ip代理后端两台ip
service就是抽象一个相对稳定的点，可以让服务有一个稳定的接入点可以接入进来
2.5.2 查看service
[root@kjdow7-21 ~]# kubectl describe svc nginx-dp -n kube-public
Name: nginx-dp
Namespace: kube-public
Labels: app=nginx-dp
Annotations: <none>
Selector: app=nginx-dp
Type: ClusterIP
IP: 192.168.208.157
Port: <unset> 80/TCP
TargetPort: 80/TCP
Endpoints: 172.7.21.3:80,172.7.22.4:80
Session Affinity: None
Events: <none>
可以看到selector跟pod一样，service是通过标签进行匹配
注意：service简写为svc
2.6 总结
- kubernetes集群管理集群资源的唯一入口是通过相应的方法调用apiserver的接口
- kubectl是官方的cli命令行工具，用于与apiserver进行通信，将用户在命令行输入的命令，组织并转化为apiserver能识别的信息，进而实现管理k8s各种资源的一种有效途径。
- kubectl的命令大全
-
- kubectl --help
- kubernetes中文社区
- 陈述式资源管理方法可以满足90%以上的资源管理需求，但它的缺点也很明显
-
- 命令冗长、复杂、难以记忆
- 特定场景下无法实现管理需求
- 对资源的增、删、查操作比较容易，改就很痛苦了
3.声明式资源管理方法
声明式资源管理方法依赖于资源配置清单（yaml/json）
3.1 查看资源配置清单的方法
[root@kjdow7-21 ~]# kubectl get svc nginx-dp -o yaml -n kube-public
apiVersion: v1
kind: Service
metadata:
creationTimestamp: "2020-01-14T17:15:32Z"
labels:
app: nginx-dp
name: nginx-dp
namespace: kube-public
resourceVersion: "649706"
selfLink: /api/v1/namespaces/kube-public/services/nginx-dp
uid: 5159828f-6d5d-4e43-83aa-51fd16b652d0
spec:
clusterIP: 192.168.208.157
ports:
- port: 80
protocol: TCP
targetPort: 80
selector:
app: nginx-dp
sessionAffinity: None
type: ClusterIP
status:
loadBalancer: {}
3.2 解释资源配置清单
[root@kjdow7-21 ~]# kubectl explain service
相当于--help，解释后面的资源是什么，怎么使用
3.3 创建资源配置清单
[root@kjdow7-21 nginx-ds]# vim nginx-ds-svc.yaml
apiVersion: v1
kind: Service
metadata:
labels:
app: nginx-ds
name: nginx-ds
namespace: default
spec:
ports:
- port: 80
protocol: TCP
targetPort: 80
selector:
app: nginx-ds
sessionAffinity: None
type: ClusterIP
[root@kjdow7-21 nginx-ds]# ls
nginx-ds-svc.yaml
[root@kjdow7-21 nginx-ds]# kubectl create -f nginx-ds-svc.yaml
service/nginx-ds created
3.4 修改资源配置清单
3.4.1 离线修改
[root@kjdow7-21 nginx-ds]# kubectl apply -f nginx-ds-svc.yaml
service/nginx-ds created
[root@kjdow7-21 nginx-ds]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 192.168.0.1 <none> 443/TCP 6d
nginx-ds ClusterIP 192.168.52.127 <none> 8080/TCP 7s
[root@kjdow7-21 nginx-ds]# vim nginx-ds-svc.yaml
###修改文件的端口为8081，并应用新的配置清单
[root@kjdow7-21 nginx-ds]# kubectl apply -f nginx-ds-svc.yaml
service/nginx-ds configured
[root@kjdow7-21 nginx-ds]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 192.168.0.1 <none> 443/TCP 6d
nginx-ds ClusterIP 192.168.52.127 <none> 8081/TCP 2m46s
注意：必须使用apply创建的，才能使用apply进行应用修改，如果是使用create进行创建的，则不能用apply应用修改
3.4.2 在线修改
[root@kjdow7-21 nginx-ds]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 192.168.0.1 <none> 443/TCP 6d
nginx-ds ClusterIP 192.168.8.104 <none> 8080/TCP 4m18s
[root@kjdow7-21 nginx-ds]# kubectl edit svc nginx-ds
service/nginx-ds edited
####通过edit相当于vim打开清单文件，修改后保存退出，立即生效，但是创建时使用的yaml文件并没有被修改
[root@kjdow7-21 nginx-ds]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 192.168.0.1 <none> 443/TCP 6d
nginx-ds ClusterIP 192.168.8.104 <none> 8082/TCP 4m42s
3.5 删除资源配置清单
3.5.1 陈述式删除
[root@kjdow7-21 nginx-ds]# kubectl delete svc nginx-ds
service "nginx-ds" deleted
3.5.2 声明式删除
[root@kjdow7-21 nginx-ds]# kubectl delete -f nginx-ds-svc.yaml
service "nginx-ds" deleted
3.6 总结
- 声明式资源管理方法依赖于统一资源配置清单文件对资源进行管理
- 对资源的管理，是通过事先定义在统一资源配置清单内，再通过陈述式命令应用到k8s集群里
- 语法格式：kubectl create/apply/delete -f /path/to/yaml
- 资源配置清单的学习方法：
-
- 多看别人（官方）写的，能读懂
- 能照着现成的文件改着用
- 遇到不懂的，善于用kubectl explain 。。。查
- 初学切记上来就无中生有，自己憋着写
二、k8s核心的插件
1.flanneld安装部署
kubernetes设计了网络模型，但却将它的实现交给了网络插件，CNI网络插件最主要的功能就是实现pod资源能够跨宿主机进行通信
创建的CNI网络插件：
- Flannel
- Calico
- Canal
- Contiv
- OpenContrail
- NSX-T
- Kub-router
1.1 下载与安装flannel
在kjdow7-21、kjdow7-22上进行部署
###下载并解压flannel
[root@kjdow7-21 ~]# cd /opt/src
[root@kjdow7-22 src]# wget https://github.com/coreos/flannel/releases/download/v0.11.0/flannel-v0.11.0-linux-amd64.tar.gz
[root@kjdow7-21 src]# mkdir /opt/flannel-v0.11.0
[root@kjdow7-21 src]# tar xf flannel-v0.11.0-linux-amd64.tar.gz -C /opt/flannel-v0.11.0/
[root@kjdow7-21 src]# ln -s /opt/flannel-v0.11.0 /opt/flannel
1.2 拷贝证书
[root@kjdow7-21 srcl]# mkdir /opt/flannel/certs
[root@kjdow7-21 srcl]# cd /opt/flannel/certs
[root@kjdow7-21 certs]# scp kjdow7-200:/opt/certs/ca.pem .
[root@kjdow7-21 certs]# scp kjdow7-200:/opt/certs/client.pem .
[root@kjdow7-21 certs]# scp kjdow7-200:/opt/certs/client-key.pem .
flannel默认是需要使用etcd做一些存储和配置的，因此需要flannel使用client证书连接etcd
1.3 配置flannel配置文件
[root@kjdow7-21 flannel]# vim /opt/flannel/subnet.env
FLANNEL_NETWORK=172.7.0.0/16
FLANNEL_SUBNET=172.7.21.1/24
FLANNEL_MTU=1500
FLANNEL_IPMASQ=false
第一行表示管理的网络，第二行表示本机的网络，在其他节点上进行配置时需要进行修改
[root@kjdow7-21 flannel]# vim /opt/flannel/flanneld.sh
#!/bin/sh
./flanneld \
--public-ip=10.4.7.21 \
--etcd-endpoints=https://10.4.7.12:2379,https://10.4.7.21:2379,https://10.4.7.22:2379 \
--etcd-keyfile=./certs/client-key.pem \
--etcd-certfile=./certs/client.pem \
--etcd-cafile=./certs/ca.pem \
--iface=eth1 \
--subnet-file=./subnet.env \
--healthz-port=2401
[root@kjdow7-21 flannel]# chmod +x flanneld.sh
注意：ip写本机ip，iface写通信的接口名，根据实际进行修改，不同节点配置略有不同
1.4 配置etcd
因为flannel需要etcd做一些存储配置，因此需要在etcd中创建有关flannel的配置
[root@kjdow7-21 flannel]# cd /opt/etcd
###查看etcd集群状态
[root@kjdow7-21 etcd]# ./etcdctl member list
988139385f78284: name=etcd-server-7-22 peerURLs=https://10.4.7.22:2380 clientURLs=http://127.0.0.1:2379,https://10.4.7.22:2379 isLeader=false
5a0ef2a004fc4349: name=etcd-server-7-21 peerURLs=https://10.4.7.21:2380 clientURLs=http://127.0.0.1:2379,https://10.4.7.21:2379 isLeader=false
f4a0cb0a765574a8: name=etcd-server-7-12 peerURLs=https://10.4.7.12:2380 clientURLs=http://127.0.0.1:2379,https://10.4.7.12:2379 isLeader=true
配置etcd，增加host-gw
[root@kjdow7-21 etcd]# ./etcdctl set /coreos.com/network/config '{"Network": "172.7.0.0/16", "Backend": {"Type": "host-gw"}}'
{"Network": "172.7.0.0/16", "Backend": {"Type": "host-gw"}}
###查看配置的内容
[root@kjdow7-21 etcd]# ./etcdctl get /coreos.com/network/config
{"Network": "172.7.0.0/16", "Backend": {"Type": "host-gw"}}
注意：这一步只需要做一次就行，不需要在其他节点重复配置了
1.5 创建supervisor配置
[root@kjdow7-21 etcd]# vi /etc/supervisord.d/flannel.ini
[program:flanneld-7-21]
command=/opt/flannel/flanneld.sh ; the program (relative uses PATH, can take args)
numprocs=1 ; number of processes copies to start (def 1)
directory=/opt/flannel ; directory to cwd to before exec (def no cwd)
autostart=true ; start at supervisord start (default: true)
autorestart=true ; retstart at unexpected quit (default: true)
startsecs=30 ; number of secs prog must stay running (def. 1)
startretries=3 ; max # of serial start failures (default 3)
exitcodes=0,2 ; 'expected' exit codes for process (default 0,2)
stopsignal=QUIT ; signal used to kill process (default TERM)
stopwaitsecs=10 ; max num secs to wait b4 SIGKILL (default 10)
user=root ; setuid to this UNIX account to run the program
redirect_stderr=true ; redirect proc stderr to stdout (default false)
stdout_logfile=/data/logs/flanneld/flanneld.stdout.log ; stderr log path, NONE for none; default AUTO
stdout_logfile_maxbytes=64MB ; max # logfile bytes b4 rotation (default 50MB)
stdout_logfile_backups=4 ; # of stdout logfile backups (default 10)
stdout_capture_maxbytes=1MB ; number of bytes in 'capturemode' (default 0)
stdout_events_enabled=false ; emit events on stdout writes (default false)
####创建日志目录
[root@kjdow7-21 flannel]# mkdir -p /data/logs/flanneld
###启动
[root@kjdow7-21 flannel]# supervisorctl update
flanneld-7-21: added process group
[root@kjdow7-21 flannel]# supervisorctl status
etcd-server-7-21 RUNNING pid 5885, uptime 4 days, 13:33:06
flanneld-7-21 RUNNING pid 10430, uptime 0:00:40
kube-apiserver-7-21 RUNNING pid 5886, uptime 4 days, 13:33:06
kube-controller-manager-7-21 RUNNING pid 5887, uptime 4 days, 13:33:06
kube-kubelet-7-21 RUNNING pid 5881, uptime 4 days, 13:33:06
kube-proxy-7-21 RUNNING pid 5890, uptime 4 days, 13:33:06
kube-scheduler-7-21 RUNNING pid 5894, uptime 4 days, 13:33:06
配置端口转发
flannel依托于端口转发功能，每台安装flannel的服务器必须配置端口转发
~]# vim /etc/sysctl.conf
net.ipv4.ip_forward = 1
sysctl -p
1.6 验证Flannel
[root@kjdow7-21 ~]# kubectl get pod -n kube-public -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-dp-67f6684bb9-lmfvl 1/1 Running 0 18h 172.7.22.4 kjdow7-22.host.com <none> <none>
nginx-dp-67f6684bb9-nn9pq 1/1 Running 0 18h 172.7.21.3 kjdow7-21.host.com <none> <none>
####在一台运算节点上ping，发现都能ping通了
[root@kjdow7-21 ~]# ping 172.7.22.4
PING 172.7.22.4 (172.7.22.4) 56(84) bytes of data.
64 bytes from 172.7.22.4: icmp_seq=1 ttl=63 time=0.528 ms
64 bytes from 172.7.22.4: icmp_seq=2 ttl=63 time=0.249 ms
^C
--- 172.7.22.4 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1000ms
rtt min/avg/max/mdev = 0.249/0.388/0.528/0.140 ms
[root@kjdow7-21 ~]# ping 172.7.21.3
PING 172.7.21.3 (172.7.21.3) 56(84) bytes of data.
64 bytes from 172.7.21.3: icmp_seq=1 ttl=64 time=0.151 ms
64 bytes from 172.7.21.3: icmp_seq=2 ttl=64 time=0.101 ms
^C
--- 172.7.21.3 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1000ms
rtt min/avg/max/mdev = 0.101/0.126/0.151/0.025 ms
注意： 通过ip可以看到这两个pod分别在两个不同的宿主机上部署着，之前不能curl通其他宿主机上的pod，现在已经可以了
1.7 flannel原理以及三种网络模型
1.7.1 Flannel的host-gw模型
###在21上看路由表
[root@kjdow7-21 ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 10.4.7.11 0.0.0.0 UG 100 0 0 eth1
10.4.7.0 0.0.0.0 255.255.255.0 U 100 0 0 eth1
172.7.21.0 0.0.0.0 255.255.255.0 U 0 0 0 docker0
172.7.22.0 10.4.7.22 255.255.255.0 UG 0 0 0 eth1
###在22上看路由表
[root@kjdow7-22 ~]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 10.4.7.11 0.0.0.0 UG 100 0 0 eth1
10.4.7.0 0.0.0.0 255.255.255.0 U 100 0 0 eth1
172.7.21.0 10.4.7.21 255.255.255.0 UG 0 0 0 eth1
172.7.22.0 0.0.0.0 255.255.255.0 U 0 0 0 docker0
可以看到flannel在host-gw模式下其实是维护了一个静态路由表，通过静态路由进行通信。
注意：此种模型仅限于所以的运算节点都在一个网段，且指向同一个网关
'{"Network": "172.7.0.0/16", "Backend": {"Type": "host-gw"}}'
1.7.2 Flannel的VxLAN模型
注意：如果运算节点不在一个网段内，则需要使用vxlan模型。其实就是先找本机接口ip，并给包添加一个flannel的包头，然后再发送出去。
'{"Network": "172.7.0.0/16", "Backend": {"Type": "VxLAN"}}'
通过VxLAN模式启动，会在宿主机上添加一个flannel.1的虚拟网络设备，例如7-21上有如下图所示的网络
1.7.3 直接路由模型
'{"Network": "172.7.0.0/16", "Backend": {"Type": "VxLAN","Directrouting": true}}'
模型是vxlan模型，但是如果发现运算节点都在一个网段，就走host-gw网络
1.8 flannel之SNAT规则优化
问题：在k8s中运行了一个deployment，并起了两个pod做web服务器，可以看到分别部署在两个节点上，登录一个pod，并使用curl访问web页面，在另一个pod上查看实时日志，发现web日志，显示访问的源ip是宿主机ip
怎么解决呢？
在kjdow7-21、kjdow7-22上进行操作
[root@kjdow7-21 ~]# yum install iptables-services -y
[root@kjdow7-21 ~]# systemctl start iptables
[root@kjdow7-21 ~]# systemctl enable iptables
——————————————————————————————————————————————————————————————————————————————
[root@kjdow7-21 ~]# iptables -t nat -D POSTROUTING -s 172.7.21.0/24 ! -o docker0 -j MASQUERADE
[root@kjdow7-21 ~]# iptables -t nat -I POSTROUTING -s 172.7.21.0/24 ! -d 172.7.0.0/16 ! -o docker0 -j MASQUERADE
[root@kjdow7-21 ~]# service iptables save
iptables: Saving firewall rules to /etc/sysconfig/iptables:[ OK ]
####10.4.7.21主机上的，来源是172.7.21.0/24段的docker的ip，目标ip不是172.7.0.0/16段，网络发包不从docker0桥设备出站的，才进行SNAT转换
——————————————————————————————————————————————————————————————————————————————
[root@kjdow7-21 ~]# iptables-save | grep -i reject
-A INPUT -j REJECT --reject-with icmp-host-prohibited
-A FORWARD -j REJECT --reject-with icmp-host-prohibited
[root@kjdow7-21 ~]# iptables -t filter -D INPUT -j REJECT --reject-with icmp-host-prohibited
[root@kjdow7-21 ~]# iptables -t filter -D FORWARD -j REJECT --reject-with icmp-host-prohibited
[root@kjdow7-21 ~]# service iptables save
iptables: Saving firewall rules to /etc/sysconfig/iptables:[ OK ]
在其中一个pod上访问另一个pod的地址，并查看另一个pod的实时日志，可以看到日志中的源地址是真实的地址
在真实生产的情况中，要根据实际情况进行优化。
2.安装部署coredns
- 简单来说，服务发现就是服务（应用）之间互相定位的过程。
- 服务发现并非云时代独有的，传统的单体架构时代也会用到。以下应用场景下，更需要服务发现
-
- 服务（应用）的动态性强
- 服务（应用）更新发布频繁
- 服务（应用）支持自动伸缩
- 在k8s集群里，POD的ip是不断变化的，如何“以不变应万变”呢？
-
- 抽象出了service资源，通过标签选择器，关联一组pod
- 抽象出了集群网络，通过相对固定的“集群ip”，使服务接入点固定
- 那么如何自动关联service资源的“名称”和“集群网络ip”，从而达到服务被集群自动发现的目的呢？
-
- 考虑传统的DNS的模型：kjdow7-21.host.com----->10.4.7.21
- 能否在k8s里建立这样的模型：nginx-ds------>192.168.0.5
- k8s里服务发现的方式-------DNS
- 实现k8s里DNS功能的插件（软件）
-
- kube-dns----------> kubernetes-v1.2至kubernetes-v1.10
- coredns------------> kubernetes-v1.11至今
- 注意：
-
- k8s里的DNS不是万能的，他应该只负责自动维护“服务名”-------> “集群网络IP”之间的关系
2.1 部署k8s的内网资源配置清单http服务
在kjdow7-200上，配置一个nginx虚拟主机，用来提供k8s统一的资源配置清单访问入口
- 配置nginx
[root@kjdow7-200 conf.d]# vim k8s-yaml.phc-dow.com.conf
server {
listen 80;
server_name k8s-yaml.phc-dow.com;
location / {
autoindex on;
default_type text/plain;
root /data/k8s-yaml;
}
}
[root@kjdow7-200 conf.d]# nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
[root@kjdow7-200 conf.d]# systemctl reload nginx
[root@kjdow7-200 conf.d]# mkdir /data/k8s-yaml -p
- 配置内网dns解析
在kjdow7-11上
[root@kjdow7-11 ~]# cd /var/named/
[root@kjdow7-11 named]# vim phc-dow.com.zon
2020010203 ; serial #serial值加一
k8s-yaml A 10.4.7.200 #添加此行记录
[root@kjdow7-11 named]# systemctl restart named
2.2 下载coredns镜像
在kjdow7-200上
###准备coredns的镜像，并推送到harbor里面
[root@kjdow7-200 ~]# docker pull coredns/coredns:1.6.1
1.6.1: Pulling from coredns/coredns
c6568d217a00: Pull complete
d7ef34146932: Pull complete
Digest: sha256:9ae3b6fcac4ee821362277de6bd8fd2236fa7d3e19af2ef0406d80b595620a7a
Status: Downloaded newer image for coredns/coredns:1.6.1
docker.io/coredns/coredns:1.6.1
[root@kjdow7-200 ~]# docker tag c0f6e815079e harbor.phc-dow.com/public/coredns:v1.6.1
[root@kjdow7-200 ~]# docker push harbor.phc-dow.com/public/coredns:v1.6.1
2.3 准备资源配置清单
在kjdow7-200上
[root@kjdow7-200 k8s-yaml]# mkdir coredns && cd /data/k8s-yaml/coredns
[root@kjdow7-200 coredns]# vim /data/k8s-yaml/coredns/rbac.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: coredns
namespace: kube-system
labels:
kubernetes.io/cluster-service: "true"
addonmanager.kubernetes.io/mode: Reconcile
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
labels:
kubernetes.io/bootstrapping: rbac-defaults
addonmanager.kubernetes.io/mode: Reconcile
name: system:coredns
rules:
- apiGroups:
- ""
resources:
- endpoints
- services
- pods
- namespaces
verbs:
- list
- watch
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
annotations:
rbac.authorization.kubernetes.io/autoupdate: "true"
labels:
kubernetes.io/bootstrapping: rbac-defaults
addonmanager.kubernetes.io/mode: EnsureExists
name: system:coredns
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: system:coredns
subjects:
- kind: ServiceAccount
name: coredns
namespace: kube-system
[root@kjdow7-200 coredns]# vim /data/k8s-yaml/coredns/cm.yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: coredns
namespace: kube-system
data:
Corefile: |
.:53 {
errors
log
health
ready
kubernetes cluster.local 192.168.0.0/16
forward . 10.4.7.11
cache 30
loop
reload
loadbalance
}
[root@kjdow7-200 coredns]# vim /data/k8s-yaml/coredns/dp.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: coredns
namespace: kube-system
labels:
k8s-app: coredns
kubernetes.io/name: "CoreDNS"
spec:
replicas: 1
selector:
matchLabels:
k8s-app: coredns
template:
metadata:
labels:
k8s-app: coredns
spec:
priorityClassName: system-cluster-critical
serviceAccountName: coredns
containers:
- name: coredns
image: harbor.phc-dow.com/public/coredns:v1.6.1
args:
- -conf
- /etc/coredns/Corefile
volumeMounts:
- name: config-volume
mountPath: /etc/coredns
ports:
- containerPort: 53
name: dns
protocol: UDP
- containerPort: 53
name: dns-tcp
protocol: TCP
- containerPort: 9153
name: metrics
protocol: TCP
livenessProbe:
httpGet:
path: /health
port: 8080
scheme: HTTP
initialDelaySeconds: 60
timeoutSeconds: 5
successThreshold: 1
failureThreshold: 5
dnsPolicy: Default
volumes:
- name: config-volume
configMap:
name: coredns
items:
- key: Corefile
path: Corefile
[root@kjdow7-200 coredns]# vim /data/k8s-yaml/coredns/svc.yaml
apiVersion: v1
kind: Service
metadata:
name: coredns
namespace: kube-system
labels:
k8s-app: coredns
kubernetes.io/cluster-service: "true"
kubernetes.io/name: "CoreDNS"
spec:
selector:
k8s-app: coredns
clusterIP: 192.168.0.2
ports:
- name: dns
port: 53
protocol: UDP
- name: dns-tcp
port: 53
- name: metrics
port: 9153
protocol: TCP
[root@kjdow7-200 coredns]# ll
total 16
-rw-r--r-- 1 root root 319 Jan 16 20:53 cm.yaml
-rw-r--r-- 1 root root 1299 Jan 16 20:57 dp.yaml
-rw-r--r-- 1 root root 954 Jan 16 20:51 rbac.yaml
-rw-r--r-- 1 root root 387 Jan 16 20:58 svc.yaml
2.4 声明式创建资源
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/coredns/rbac.yaml
serviceaccount/coredns created
clusterrole.rbac.authorization.k8s.io/system:coredns created
clusterrolebinding.rbac.authorization.k8s.io/system:coredns created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/coredns/cm.yaml
configmap/coredns created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/coredns/dp.yaml
deployment.apps/coredns created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/coredns/svc.yaml
service/coredns created
[root@kjdow7-21 ~]# kubectl get all -n kube-system
NAME READY STATUS RESTARTS AGE
pod/coredns-7dd986bcdc-2w8nw 1/1 Running 0 119s
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/coredns ClusterIP 192.168.0.2 <none> 53/UDP,53/TCP,9153/TCP 112s
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/coredns 1/1 1 1 119s
NAME DESIRED CURRENT READY AGE
replicaset.apps/coredns-7dd986bcdc 1 1 1 119s
[root@kjdow7-21 ~]# dig -t A www.baidu.com @192.168.0.2 +short
www.a.shifen.com.
180.101.49.12
180.101.49.11
[root@kjdow7-21 ~]# dig -t A kjdow7-21.host.com @192.168.0.2 +short
10.4.7.21
注意：在前面kubelet的启动脚本中已经制定了dns的ip是192.168.0.2，因此这里可以解析
2.5 验证
[root@kjdow7-21 ~]# kubectl get all -n kube-public
NAME READY STATUS RESTARTS AGE
pod/nginx-dp-5595d547b4-9hc8h 1/1 Running 0 40h
pod/nginx-dp-5595d547b4-zdwxl 1/1 Running 0 40h
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/nginx-dp ClusterIP 192.168.208.157 <none> 80/TCP 2d16h
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/nginx-dp 2/2 2 2 2d16h
NAME DESIRED CURRENT READY AGE
replicaset.apps/nginx-dp-5595d547b4 2 2 2 40h
replicaset.apps/nginx-dp-67f6684bb9 0 0 0 2d16h
[root@kjdow7-21 ~]# dig -t A nginx-dp.kube-public.svc.cluster.local. @192.168.0.2 +short
192.168.208.157
[root@kjdow7-21 ~]# kubectl exec -it nginx-dp-5595d547b4-9hc8h /bin/bash -n kube-public
root@nginx-dp-5595d547b4-9hc8h:/# cat /etc/resolv.conf
nameserver 192.168.0.2
search kube-public.svc.cluster.local svc.cluster.local cluster.local host.com
options ndots:5
###进入pod可以看到容器的dns已经自动设置为192.168.0.2
3.k8s服务暴露之ingress
- k8s的DNS实现了服务在集群内被自动发现，那如何使得服务在k8s集群外被使用和访问呢？
-
- 使用nodeport型的service
-
- 注意：无法使用kube-proxy的ipvs模型，只能使用iptables模型
- 使用ingress资源
-
- Ingress只能调度并暴露7层应用，特指http和https协议
- Ingress是K8S API的标准资源类型之一，也是一种核心资源，它其实就是一组基于域名和URL路径，把用户的请求转发至指定的service资源的规则
- 可以将集群外部的请求流量，转发至集群内部，从而实现服务暴露
- Ingress控制器是能够为Ingress资源监听某套接字，然后根据Ingress规则匹配机制路由调度流量的一个组件
- 说白了，Ingress没啥神秘的，就是个简化版的nginx+一段go脚本而已
- 常用的Ingress控制器的实现软件
-
- Ingress-nginx
- HAProxy
- Traefik
3.1 部署traefik（ingress控制器）---准备traefik镜像
[root@kjdow7-200 ~]# docker pull traefik:v1.7.2-alpine
v1.7.2-alpine: Pulling from library/traefik
4fe2ade4980c: Pull complete
8d9593d002f4: Pull complete
5d09ab10efbd: Pull complete
37b796c58adc: Pull complete
Digest: sha256:cf30141936f73599e1a46355592d08c88d74bd291f05104fe11a8bcce447c044
Status: Downloaded newer image for traefik:v1.7.2-alpine
docker.io/library/traefik:v1.7.2-alpine
[root@kjdow7-200 ~]# docker images | grep traefik
traefik v1.7.2-alpine add5fac61ae5 15 months ago 72.4MB
[root@kjdow7-200 ~]# docker tag traefik:v1.7.2-alpine harbor.phc-dow.com/public/traefik:v1.7.2-alpine
[root@kjdow7-200 ~]# docker push harbor.phc-dow.com/public/traefik:v1.7.2-alpine
The push refers to repository [harbor.phc-dow.com/public/traefik]
a02beb48577f: Pushed
ca22117205f4: Pushed
3563c211d861: Pushed
df64d3292fd6: Pushed
v1.7.2-alpine: digest: sha256:6115155b261707b642341b065cd3fac2b546559ba035d0262650b3b3bbdd10ea size: 1157
3.2 准备资源配置清单
[root@kjdow7-200 ~]# mkdir /data/k8s-yaml/traefik
[root@kjdow7-200 ~]# cat /data/k8s-yaml/traefik/rbac.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: traefik-ingress-controller
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
name: traefik-ingress-controller
rules:
- apiGroups:
- ""
resources:
- services
- endpoints
- secrets
verbs:
- get
- list
- watch
- apiGroups:
- extensions
resources:
- ingresses
verbs:
- get
- list
- watch
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: traefik-ingress-controller
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: traefik-ingress-controller
subjects:
- kind: ServiceAccount
name: traefik-ingress-controller
namespace: kube-system
[root@kjdow7-200 ~]# cat /data/k8s-yaml/traefik/ds.yaml
apiVersion: extensions/v1beta1
kind: DaemonSet
metadata:
name: traefik-ingress
namespace: kube-system
labels:
k8s-app: traefik-ingress
spec:
template:
metadata:
labels:
k8s-app: traefik-ingress
name: traefik-ingress
spec:
serviceAccountName: traefik-ingress-controller
terminationGracePeriodSeconds: 60
containers:
- image: harbor.phc-dow.com/public/traefik:v1.7.2-alpine
name: traefik-ingress
ports:
- name: controller
containerPort: 80
hostPort: 81
- name: admin-web
containerPort: 8080
securityContext:
capabilities:
drop:
- ALL
add:
- NET_BIND_SERVICE
args:
- --api
- --kubernetes
- --logLevel=INFO
- --insecureskipverify=true
- --kubernetes.endpoint=https://10.4.7.10:7443
- --accesslog
- --accesslog.filepath=/var/log/traefik_access.log
- --traefiklog
- --traefiklog.filepath=/var/log/traefik.log
- --metrics.prometheus
[root@kjdow7-200 ~]# cat /data/k8s-yaml/traefik/svc.yaml
kind: Service
apiVersion: v1
metadata:
name: traefik-ingress-service
namespace: kube-system
spec:
selector:
k8s-app: traefik-ingress
ports:
- protocol: TCP
port: 80
name: controller
- protocol: TCP
port: 8080
name: admin-web
[root@kjdow7-200 ~]# cat /data/k8s-yaml/traefik/ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: traefik-web-ui
namespace: kube-system
annotations:
kubernetes.io/ingress.class: traefik
spec:
rules:
- host: traefik.phc-dow.com
http:
paths:
- path: /
backend:
serviceName: traefik-ingress-service
servicePort: 8080
3.3 创建资源
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/traefik/rbac.yaml
serviceaccount/traefik-ingress-controller created
clusterrole.rbac.authorization.k8s.io/traefik-ingress-controller created
clusterrolebinding.rbac.authorization.k8s.io/traefik-ingress-controller created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/traefik/ds.yaml
daemonset.extensions/traefik-ingress created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/traefik/svc.yaml
service/traefik-ingress-service created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/traefik/ingress.yaml
ingress.extensions/traefik-web-ui created
注意：使用kubectl get pod -n kube-system,traefik这个pod可能会停留在containercreating的状态，并报错
Warning FailedCreatePodSandBox 15m kubelet, kjdow7-21.host.com Failed create pod sandbox: rpc error: code = Unknown desc = failed to start sandbox container for pod "traefik-ingress-7fsp8": Error response from daemon: driver failed programming external connectivity on endpoint k8s_POD_traefik-ingress-7fsp8_kube-system_3c7fbecb-801c-4f3a-aa30-e3717245d9f5_0 (7603ab3cbc43915876ab0db527195a963f8c8f4a59f8a1a84f00332f3f387227): (iptables failed: iptables --wait -t filter -A DOCKER ! -i docker0 -o docker0 -p tcp -d 172.7.21.5 --dport 80 -j ACCEPT: iptables: No chain/target/match by that name. (exit status 1))这时可以重启kubelet服务
按照配置已经监听了宿主机的81端口
[root@kjdow7-21 ~]# netstat -lntup | grep 81
tcp6 0 0 :::81 :::* LISTEN 25625/docker-proxy
[root@kjdow7-22 ~]# netstat -lntup | grep 81
tcp6 0 0 :::81 :::* LISTEN 22080/docker-proxy
3.5 配置反向代理
[root@kjdow7-11 ~]# cat /etc/nginx/conf.d/phc-dow.com.conf
upstream default_backend_traefik {
server 10.4.7.21:81 max_fails=3 fail_timeout=10s;
server 10.4.7.22:81 max_fails=3 fail_timeout=10s;
}
server {
server_name *.phc-dow.com;
location / {
proxy_pass http://default_backend_traefik;
proxy_set_header Host $http_host;
proxy_set_header x-forwarded-for $proxy_add_x_forwarded_for;
}
}
[root@kjdow7-11 ~]# systemctl reload nginx
3.6 添加域名解析
[root@kjdow7-11 conf.d]# vim /var/named/phc-dow.com.zone
$ORIGIN phc-dow.com.
$TTL 600 ; 10 minutes
@ IN SOA dns.phc-dow.com. dnsadmin.phc-dow.com. (
2020010204 ; serial #serial值+1
10800 ; refresh (3 hours)
900 ; retry (15 minutes)
604800 ; expire (1 week)
86400 ; minimum (1 day)
)
NS dns.phc-dow.com.
$TTL 60 ; 1 minute
dns A 10.4.7.11
harbor A 10.4.7.200
k8s-yaml A 10.4.7.200
traefik A 10.4.7.10 #添加此行配置
[root@kjdow7-11 conf.d]# systemctl restart named
[root@kjdow7-11 conf.d]# dig -t A traefik,phc-dow.com @10.4.7.11 +short
[root@kjdow7-11 conf.d]# dig -t A traefik.phc-dow.com @10.4.7.11 +short
10.4.7.10
访问域名：traefik.phc-dow.com
4.dashboar插件安装部署
4.1 准备dashboard镜像
[root@kjdow7-200 ~]# docker pull k8scn/kubernetes-dashboard-amd64:v1.8.3
[root@kjdow7-200 ~]# docker images | grep dashboard
k8scn/kubernetes-dashboard-amd64 v1.8.3 fcac9aa03fd6 19 months ago 102MB
[root@kjdow7-200 ~]# docker tag fcac9aa03fd6 harbor.phc-dow.com/public/dashboard:v1.8.3
[root@kjdow7-200 ~]# docker push harbor.phc-dow.com/public/dashboard:v1.8.3
4.2 准备资源配置清单
可以参考github中kubernetes下cluster/addons/dashboard/这里有官方提供的yaml模板
[root@kjdow7-200 ~]# mkdir -p /data/k8s-yaml/dashboard
[root@kjdow7-200 ~]# cat /data/k8s-yaml/dashboard/rbac.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
labels:
k8s-app: kubernetes-dashboard
addonmanager.kubernetes.io/mode: Reconcile
name: kubernetes-dashboard-admin
namespace: kube-system
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: kubernetes-dashboard-admin
namespace: kube-system
labels:
k8s-app: kubernetes-dashboard
addonmanager.kubernetes.io/mode: Reconcile
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: cluster-admin
subjects:
- kind: ServiceAccount
name: kubernetes-dashboard-admin
namespace: kube-system
[root@kjdow7-200 ~]# cat /data/k8s-yaml/dashboard/dp.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: kubernetes-dashboard
namespace: kube-system
labels:
k8s-app: kubernetes-dashboard
kubernetes.io/cluster-service: "true"
addonmanager.kubernetes.io/mode: Reconcile
spec:
selector:
matchLabels:
k8s-app: kubernetes-dashboard
template:
metadata:
labels:
k8s-app: kubernetes-dashboard
annotations:
scheduler.alpha.kubernetes.io/critical-pod: ''
spec:
priorityClassName: system-cluster-critical
containers:
- name: kubernetes-dashboard
image: harbor.phc-dow.com/public/dashboard:v1.8.3
resources:
limits:
cpu: 100m
memory: 300Mi
requests:
cpu: 50m
memory: 100Mi
ports:
- containerPort: 8443
protocol: TCP
args:
# PLATFORM-SPECIFIC ARGS HERE
- --auto-generate-certificates
volumeMounts:
- name: tmp-volume
mountPath: /tmp
livenessProbe:
httpGet:
scheme: HTTPS
path: /
port: 8443
initialDelaySeconds: 30
timeoutSeconds: 30
volumes:
- name: tmp-volume
emptyDir: {}
serviceAccountName: kubernetes-dashboard-admin
tolerations:
- key: "CriticalAddonsOnly"
operator: "Exists"
[root@kjdow7-200 dashboard]# cat svc.yaml
apiVersion: v1
kind: Service
metadata:
name: kubernetes-dashboard
namespace: kube-system
labels:
k8s-app: kubernetes-dashboard
kubernetes.io/cluster-service: "true"
addonmanager.kubernetes.io/mode: Reconcile
spec:
selector:
k8s-app: kubernetes-dashboard
ports:
- port: 443
targetPort: 8443
[root@kjdow7-200 ~]# cat /data/k8s-yaml/dashboard/ingress.yaml
apiVersion: extensions/v1beta1
kind: Ingress
metadata:
name: kubernetes-dashboard
namespace: kube-system
annotations:
kubernetes.io/ingress.class: traefik
spec:
rules:
- host: dashboard.phc-dow.com
http:
paths:
- backend:
serviceName: kubernetes-dashboard
servicePort: 443
4.3 创建资源
[root@kjdow7-22 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/rbac.yaml
serviceaccount/kubernetes-dashboard-admin created
clusterrolebinding.rbac.authorization.k8s.io/kubernetes-dashboard-admin created
[root@kjdow7-22 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/dp.yaml
deployment.apps/kubernetes-dashboard created
[root@kjdow7-22 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/svc.yaml
service/kubernetes-dashboard created
[root@kjdow7-22 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/ingress.yaml
ingress.extensions/kubernetes-dashboard created
[root@kjdow7-22 ~]# kubectl get pod -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-7dd986bcdc-2w8nw 1/1 Running 0 3d22h
kubernetes-dashboard-857c754c78-fv5k6 1/1 Running 0 72s
traefik-ingress-7fsp8 1/1 Running 0 2d20h
traefik-ingress-rlwrj 1/1 Running 0 2d20h
[root@kjdow7-22 ~]# kubectl get svc -n kube-system
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
coredns ClusterIP 192.168.0.2 <none> 53/UDP,53/TCP,9153/TCP 3d22h
kubernetes-dashboard ClusterIP 192.168.75.142 <none> 443/TCP 2m32s
traefik-ingress-service ClusterIP 192.168.58.5 <none> 80/TCP,8080/TCP 2d20h
[root@kjdow7-22 ~]# kubectl get ingress -n kube-system
NAME HOSTS ADDRESS PORTS AGE
kubernetes-dashboard dashboard.phc-dow.com 80 2m30s
traefik-web-ui traefik.phc-dow.com 80 2d20h
4.4 添加域名解析
[root@kjdow7-11 ~]# cat /var/named/phc-dow.com.zone
$ORIGIN phc-dow.com.
$TTL 600 ; 10 minutes
@ IN SOA dns.phc-dow.com. dnsadmin.phc-dow.com. (
2020010205 ; serial #值加一
10800 ; refresh (3 hours)
900 ; retry (15 minutes)
604800 ; expire (1 week)
86400 ; minimum (1 day)
)
NS dns.phc-dow.com.
$TTL 60 ; 1 minute
dns A 10.4.7.11
harbor A 10.4.7.200
k8s-yaml A 10.4.7.200
traefik A 10.4.7.10
dashboard A 10.4.7.10 #添加A记录
[root@kjdow7-11 ~]# systemctl restart named
[root@kjdow7-11 ~]# dig -t A dashboard.phc-dow.com @10.4.7.11 +short
10.4.7.10
[root@kjdow7-21 ~]# dig -t A dashboard.phc-dow.com @192.168.0.2 +shor
10.4.7.10
4.5 dashboard配置配置https访问并登录
[root@kjdow7-200 ~]# cd /opt/certs/
[root@kjdow7-200 certs]# (umask 077; openssl genrsa -out dashboard.phc-dow.com.key 2048)
Generating RSA private key, 2048 bit long modulus
...............................................+++
...........................+++
e is 65537 (0x10001)
[root@kjdow7-200 certs]# openssl req -new -key dashboard.phc-dow.com.key -out dashboard.phc-dow.com.csr -subj "/CN=dashboard.phc-dow.com/C=CN/ST=SH/L=Shanghai/O=kjdow/OU=kj"
[root@kjdow7-200 certs]# openssl x509 -req -in dashboard.phc-dow.com.csr -CA ca.pem -CAkey ca-key.pem -CAcreateserial -out dashboard.phc-dow.com.crt -days 3650
Signature ok
subject=/CN=dashboard.phc-dow.com/C=CN/ST=SH/L=Shanghai/O=kjdow/OU=kj
Getting CA Private Key
[root@kjdow7-200 certs]# ls -l| grep dashboard
-rw-r--r-- 1 root root 1212 Jan 20 23:59 dashboard.phc-dow.com.crt
-rw-r--r-- 1 root root 1009 Jan 20 23:53 dashboard.phc-dow.com.csr
-rw------- 1 root root 1679 Jan 20 23:48 dashboard.phc-dow.com.key
在kjdow7-11上配置nginx，dashborad.phc-dow.com使用https访问
[root@kjdow7-11 ~]# mkdir /etc/nginx/certs
[root@kjdow7-11 nginx]# cd /etc/nginx/certs
[root@kjdow7-11 certs]# scp 10.4.7.200:/opt/certs/dashboard.phc-dow.com.crt .
[root@kjdow7-11 certs]# scp 10.4.7.200:/opt/certs/dashboard.phc-dow.com.key .
[root@kjdow7-11 conf.d]# cat dashboard.phc-dow.conf
server {
listen 80;
server_name dashboard.phc-dow.com;
rewrite ^(.*)$ https://${server_name}$1 permanent;
}
server {
listen 443 ssl;
server_name dashboard.phc-dow.com;
ssl_certificate "certs/dashboard.phc-dow.com.crt";
ssl_certificate_key "certs/dashboard.phc-dow.com.key";
ssl_session_cache shared:SSL:1m;
ssl_session_timeout 10m;
ssl_ciphers HIGH:!aNULL:!MD5;
ssl_prefer_server_ciphers on;
location / {
proxy_pass http://default_backend_traefik;
proxy_set_header Host $http_host;
proxy_set_header x-forwarded-for $proxy_add_x_forwarded_for;
}
}
[root@kjdow7-11 conf.d]# nginx -t
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
[root@kjdow7-11 conf.d]# systemctl reload nginx
4.6 使用token登录dashboard
[root@kjdow7-21 ~]# kubectl get secret -n kube-system
NAME TYPE DATA AGE
coredns-token-xr65q kubernetes.io/service-account-token 3 4d2h
default-token-4gfv2 kubernetes.io/service-account-token 3 11d
kubernetes-dashboard-admin-token-c55cw kubernetes.io/service-account-token 3 4h27m
kubernetes-dashboard-key-holder Opaque 2 4h26m
traefik-ingress-controller-token-p9jp6 kubernetes.io/service-account-token 3 3d1h
[root@kjdow7-21 ~]# kubectl describe secret kubernetes-dashboard-admin-token-c55cw -n kube-system
Name: kubernetes-dashboard-admin-token-c55cw
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name: kubernetes-dashboard-admin
kubernetes.io/service-account.uid: de6430a5-5d41-4916-917d-23f39a47c9a0
Type: kubernetes.io/service-account-token
Data
====
ca.crt: 1379 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJrdWJlcm5ldGVzLWRhc2hib2FyZC1hZG1pbi10b2tlbi1jNTVjdyIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJrdWJlcm5ldGVzLWRhc2hib2FyZC1hZG1pbiIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6ImRlNjQzMGE1LTVkNDEtNDkxNi05MTdkLTIzZjM5YTQ3YzlhMCIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDprdWJlLXN5c3RlbTprdWJlcm5ldGVzLWRhc2hib2FyZC1hZG1pbiJ9.3FdxCC2-u7635hsifG57G0fR4kqnJPD5ARRGQXBfu47cEgCNbJMAceeW6f8Lmq_Acz_nQxaH92dVFuuouxJvBY1hrswQJMYb2qeH5icH-zZ3ivuzaZ9WFsiix-40w8itMvkv4EhQv8dGaId0DdkPxE0lo-OVUhfk3dndRZnLVPhmkBC-ciJEoaFUgjejaoLoEHx1lMXurVfd5BICPP_hGfeg5sA0HSUaUwp14oAOcbR6syHlCH3O5FN6q7Mxie9g0zqHvGc5RvyLWEKyYwbJwLPA2MeJxRmJ4wH6573w9yaOVEFvENMO-_yjJhIi1BL3MGDvtqWv35yk-jsLo5emVg
复制最后token字段的值，并粘贴到下图所示的位置
4.7 dashboard升级1.10.1
###下载最新版镜像
[root@kjdow7-200 ~]# docker pull hexun/kubernetes-dashboard-amd64:v1.10.1
v1.10.1: Pulling from hexun/kubernetes-dashboard-amd64
9518d8afb433: Pull complete
Digest: sha256:0ae6b69432e78069c5ce2bcde0fe409c5c4d6f0f4d9cd50a17974fea38898747
Status: Downloaded newer image for hexun/kubernetes-dashboard-amd64:v1.10.1
docker.io/hexun/kubernetes-dashboard-amd64:v1.10.1
[root@kjdow7-200 ~]# docker images | grep dashboard
hexun/kubernetes-dashboard-amd64 v1.10.1 f9aed6605b81 13 months ago 122MB
[root@kjdow7-200 ~]# docker tag f9aed6605b81 harbor.phc-dow.com/public/dashboard:v1.10.1
[root@kjdow7-200 ~]# docker push harbor.phc-dow.com/public/dashboard:v1.10.1
###修改dashboard的dp.yaml文件
[root@kjdow7-200 ~]# cd /data/k8s-yaml/dashboard/
[root@kjdow7-200 ~]# sed -i s#dashboard:v1.8.3#dashboard:v1.10.1#g dp.yaml
#修改dp中使用的image
###应用最新配置
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/dp.yaml
deployment.apps/kubernetes-dashboard configured
等待几秒刷新页面即可，1.10.1如果不登录是进不去的。是没有跳过选项的
4.8 创建最小权限的ServiceAccount
###创建资源配置文件
[root@kjdow7-200 dashboard]# cat /data/k8s-yaml/dashboard/rbac-minimal.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
labels:
k8s-app: kubernetes-dashboard
addonmanager.kubernetes.io/mode: Reconcile
name: kubernetes-dashboard
namespace: kube-system
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
labels:
k8s-app: kubernetes-dashboard
addonmanager.kubernetes.io/mode: Reconcile
name: kubernetes-dashboard-minimal
namespace: kube-system
rules:
# Allow Dashboard to get, update and delete Dashboard exclusive secrets.
- apiGroups: [""]
resources: ["secrets"]
resourceNames: ["kubernetes-dashboard-key-holder", "kubernetes-dashboard-certs"]
verbs: ["get", "update", "delete"]
# Allow Dashboard to get and update 'kubernetes-dashboard-settings' config map.
- apiGroups: [""]
resources: ["configmaps"]
resourceNames: ["kubernetes-dashboard-settings"]
verbs: ["get", "update"]
# Allow Dashboard to get metrics from heapster.
- apiGroups: [""]
resources: ["services"]
resourceNames: ["heapster"]
verbs: ["proxy"]
- apiGroups: [""]
resources: ["services/proxy"]
resourceNames: ["heapster", "http:heapster:", "https:heapster:"]
verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: kubernetes-dashboard-minimal
namespace: kube-system
labels:
k8s-app: kubernetes-dashboard
addonmanager.kubernetes.io/mode: Reconcile
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: kubernetes-dashboard-minimal
subjects:
- kind: ServiceAccount
name: kubernetes-dashboard
namespace: kube-system
[root@kjdow7-200 dashboard]# sed -i s#"serviceAccountName: kubernetes-dashboard-admin"#"serviceAccountName: kubernetes-dashboard"#g dp.yaml
#修改绑定的服务用户名
###应用配置
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/rbac-minimal.yaml
serviceaccount/kubernetes-dashboard created
role.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created
rolebinding.rbac.authorization.k8s.io/kubernetes-dashboard-minimal created
[root@kjdow7-21 ~]# kubectl get pod -n kube-system
NAME READY STATUS RESTARTS AGE
coredns-7dd986bcdc-2w8nw 1/1 Running 0 4d5h
kubernetes-dashboard-7f5f8dd677-knlrs 1/1 Running 0 6s
kubernetes-dashboard-d9d98bb89-2jmmx 0/1 Terminating 0 38m
traefik-ingress-7fsp8 1/1 Running 0 3d3h
traefik-ingress-rlwrj 1/1 Running 0 3d3h
#可以看到新的pod已经启动，老的pod正在删除
查看新的服务用户名的令牌，并登录
[root@kjdow7-21 ~]# kubectl get secret -n kube-system
NAME TYPE DATA AGE
coredns-token-xr65q kubernetes.io/service-account-token 3 4d5h
default-token-4gfv2 kubernetes.io/service-account-token 3 11d
kubernetes-dashboard-admin-token-c55cw kubernetes.io/service-account-token 3 6h58m
kubernetes-dashboard-key-holder Opaque 2 6h58m
kubernetes-dashboard-token-xnvct kubernetes.io/service-account-token 3 11m
traefik-ingress-controller-token-p9jp6 kubernetes.io/service-account-token 3 3d3h
[root@kjdow7-21 ~]# kubectl describe secret kubernetes-dashboard-token-xnvct -n kube-system
Name: kubernetes-dashboard-token-xnvct
Namespace: kube-system
Labels: <none>
Annotations: kubernetes.io/service-account.name: kubernetes-dashboard
kubernetes.io/service-account.uid: 5d14b8fb-9b64-4e5b-ad49-13ac04cf44be
Type: kubernetes.io/service-account-token
Data
====
ca.crt: 1379 bytes
namespace: 11 bytes
token: eyJhbGciOiJSUzI1NiIsImtpZCI6IiJ9.eyJpc3MiOiJrdWJlcm5ldGVzL3NlcnZpY2VhY2NvdW50Iiwia3ViZXJuZXRlcy5pby9zZXJ2aWNlYWNjb3VudC9uYW1lc3BhY2UiOiJrdWJlLXN5c3RlbSIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VjcmV0Lm5hbWUiOiJrdWJlcm5ldGVzLWRhc2hib2FyZC10b2tlbi14bnZjdCIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50Lm5hbWUiOiJrdWJlcm5ldGVzLWRhc2hib2FyZCIsImt1YmVybmV0ZXMuaW8vc2VydmljZWFjY291bnQvc2VydmljZS1hY2NvdW50LnVpZCI6IjVkMTRiOGZiLTliNjQtNGU1Yi1hZDQ5LTEzYWMwNGNmNDRiZSIsInN1YiI6InN5c3RlbTpzZXJ2aWNlYWNjb3VudDprdWJlLXN5c3RlbTprdWJlcm5ldGVzLWRhc2hib2FyZCJ9.qs1oTLOPUuufo5rJC6QkS09tGUBVHd21xqR4BfOU7QLv5Ua_thlFDVps5V1pznFTyk7hV_9pN9BmZ6GPecuF2eWiwUm-sLv5gf0lg1kvO3ObO9R1RJ8AuJ6slNXJwlpQC8H0jRK2QYgLEWvnF1_tHH2F0ZTmyqBnf_O-rMrwQvLr4FGEmiZ3yf_yI6V7gNwZ_TdWTrcxpaVZk8urpmucda-o9IToy98I0MrDe1EfLJrMl_YIBppmMJFFfTgArQ7IFVQ0STlpqKY6OKV8pTXXnuUnTuD0BzLxfXQfUMo-otQdSxvhQEr8vM5vC5zrvlnBkGqJ15ctQgT0qshAcENBJg
复制最后的token字段的值，并粘贴到dashboard的web页面对应处，并登录
可以看到已经登录成功了，但是因为我们配置的是官方提供的最小的权限，因此会报错没有权限
注意：
1.在1.8.3版本中，如果点击跳过，进去之后的默认权限就是在dp.yaml配置文件中绑定的默认serviceaccountname。
2.如果用之前配置的用户也可以登录，因为这个角色已经绑定了serviceaccountname
4.9 K8S之RBAC原理
- k8s自1.6版本起默认使用基于角色的访问控制（RBAC）
- 它实现了对集群中的资源的权限的完整覆盖
- 支持权限的动态调整，无需重启apiserver
对用户资源权限的管理以dashboard进行举例
- 一共有三种对象，分别是账户、角色、权限。
- 在定义角色时赋予权限，然后角色绑定给账户，那么账户就有了相应的权限，一个账户可以绑定多个角色，可以方便进行多权限的灵活控制。
- 一个角色都唯一对应了secret，然后通过查看secret的详细信息，找到token字段，使用token的值进行登录，那么就有了这个角色所对应的权限
-
- kubectl get secret -n kube-system #查看secret
- kubectl describe secret kubernetes-dashboard-token-xnvct -n kube-system #查看指定secret的详细信息，并复制token值，进行登录
- 账户分为用户账户和服务账户
- 角色分为role和clusterrole。
- 绑定角色就有两种，分别是rolebinding和clusterrolebinding
5.dashboard插件-heapster
5.1 准备heapster镜像
在kjdow7-200上部署
[root@kjdow7-200 ~]# docker pull quay.io/bitnami/heapster:1.5.4
[root@kjdow7-200 ~]# docker images | grep heapster
quay.io/bitnami/heapster 1.5.4 c359b95ad38b 11 months ago 136MB
[root@kjdow7-200 ~]# docker tag c359b95ad38b harbor.phc-dow.com/public/heapster:v1.5.4
[root@kjdow7-200 ~]# docker push harbor.phc-dow.com/public/heapster:v1.5.4
5.2 准备资源配置清单
在kjdow7-200上部署
[root@kjdow7-200 ~]# mkdir /data/k8s-yaml/dashboard/heapster
[root@kjdow7-200 ~]# vi /data/k8s-yaml/dashboard/heapster/rbac.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: heapster
namespace: kube-system
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: heapster
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: ClusterRole
name: system:heapster
subjects:
- kind: ServiceAccount
name: heapster
namespace: kube-system
[root@kjdow7-200 ~]# vi /data/k8s-yaml/dashboard/heapster/deployment.yaml
apiVersion: extensions/v1beta1
kind: Deployment
metadata:
name: heapster
namespace: kube-system
spec:
replicas: 1
template:
metadata:
labels:
task: monitoring
k8s-app: heapster
spec:
serviceAccountName: heapster
containers:
- name: heapster
image: harbor.phc-dow.com/public/heapster:v1.5.4
imagePullPolicy: IfNotPresent
command:
- /opt/bitnami/heapster/bin/heapster
- --source=kubernetes:https://kubernetes.default
[root@kjdow7-200 ~]# vi /data/k8s-yaml/dashboard/heapster/svc.yaml
apiVersion: v1
kind: Service
metadata:
labels:
task: monitoring
# For use as a Cluster add-on (https://github.com/kubernetes/kubernetes/tree/master/cluster/addons)
# If you are NOT using this as an addon, you should comment out this line.
kubernetes.io/cluster-service: 'true'
kubernetes.io/name: Heapster
name: heapster
namespace: kube-system
spec:
ports:
- port: 80
targetPort: 8082
selector:
k8s-app: heapster
5.3 应用资源配置清单
在任意运算节点上部署
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/heapster/rbac.yaml
serviceaccount/heapster created
clusterrolebinding.rbac.authorization.k8s.io/heapster created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/heapster/deployment.yaml
deployment.extensions/heapster created
[root@kjdow7-21 ~]# kubectl apply -f http://k8s-yaml.phc-dow.com/dashboard/heapster/svc.yaml
service/heapster created
[root@kjdow7-21 ~]# kubectl get pod -n kube-system -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
coredns-7dd986bcdc-rq9dz 1/1 Running 0 26h 172.7.21.3 kjdow7-21.host.com <none> <none>
heapster-96d7f656f-4xw5k 1/1 Running 0 88s 172.7.21.4 kjdow7-21.host.com <none> <none>
kubernetes-dashboard-7f5f8dd677-knlrs 1/1 Running 0 8d 172.7.22.5 kjdow7-22.host.com <none> <none>
traefik-ingress-7fsp8 1/1 Running 0 11d 172.7.21.5 kjdow7-21.host.com <none> <none>
traefik-ingress-rlwrj 1/1 Running 0 11d 172.7.22.4 kjdow7-22.host.com <none> <none>
