kubernetes 1.17.2 结合 Ceph 13.2.8 实现 静态 动态存储 并附带一个实验
检查集群状态
kubernetes集群
# kubectl get nodes
NAME STATUS ROLES AGE VERSION
20.0.0.201 Ready,SchedulingDisabled master 31h v1.17.2
20.0.0.202 Ready,SchedulingDisabled master 31h v1.17.2
20.0.0.203 Ready,SchedulingDisabled master 31h v1.17.2
20.0.0.204 Ready node 31h v1.17.2
20.0.0.205 Ready node 31h v1.17.2
20.0.0.206 Ready node 31h v1.17.2
# kubectl get pods --all-namespaces
NAMESPACE NAME READY STATUS RESTARTS AGE
kube-system calico-kube-controllers-6cf5b744d7-rxt86 / Running 25h
kube-system calico-node-25dlc / Running 30h
kube-system calico-node-49q4n / Running 30h
kube-system calico-node-4gmcp / Running 30h
kube-system calico-node-gt4bt / Running 30h
kube-system calico-node-svcdj / Running 30h
kube-system calico-node-tkrqt / Running 30h
kube-system coredns-76b74f549-dkjxd / Running 25h
kube-system dashboard-metrics-scraper-64c8c7d847-dqbx2 / Running 24h
kube-system kubernetes-dashboard-85c79db674-bnvlk / Running 24h
kube-system metrics-server-6694c7dd66-hsbzb / Running 25h
kube-system traefik-ingress-controller-m8jf9 / Running 25h
kube-system traefik-ingress-controller-r7cgl / Running 25h
ceph集群
# ceph -s
cluster:
id: ed4d59da-c861-4da0-bbe2-8dfdea5be796
health: HEALTH_WARN
clock skew detected on mon.bs-k8s-gitlab, mon.bs-k8s-ceph
原因：一个是mon节点上ntp服务器未启动，另一个是ceph设置的mon的时间偏差阈值比较小，排查时也应遵循先第一个原因，后第二个原因的方式
# cp ceph.conf ceph.conf-`date +%F`
diff ceph.conf ceph.conf-`date +%F`
,18d16
< mon clock drift allowed =
< mon clock drift warn backoff =
# ceph-deploy --overwrite-conf config push bs-k8s-ceph bs-k8s-harbor bs-k8s-gitlab
重启mon服务
systemctl restart ceph-mon.target
# ceph -s
cluster:
id: ed4d59da-c861-4da0-bbe2-8dfdea5be796
health: HEALTH_OK
验证ceph集群和kubernetes集群都处于正常状态
kubernetes集群安装ceph客户端
bs-k8s-ceph
# scp /etc/yum.repos.d/ceph.repo 20.0.0.201:/etc/yum.repos.d/
# scp /etc/yum.repos.d/ceph.repo 20.0.0.202:/etc/yum.repos.d/
#scp /etc/yum.repos.d/ceph.repo 20.0.0.203:/etc/yum.repos.d/
#scp /etc/yum.repos.d/ceph.repo 20.0.0.204:/etc/yum.repos.d/
#scp /etc/yum.repos.d/ceph.repo 20.0.0.205:/etc/yum.repos.d/
#scp /etc/yum.repos.d/ceph.repo 20.0.0.206:/etc/yum.repos.d/
安装ceph client k8s集群操作
# yum install -y ceph
拷贝集群配置信息和 admin 密钥
[root@bs-k8s-cephlab ceph]# scp ceph.conf ceph.client.admin.keyring 20.0.0.206:/etc/ceph/
# ceph -s
cluster:
id: ed4d59da-c861-4da0-bbe2-8dfdea5be796
health: HEALTH_OK
客户端部署完成
部署一个常用的测试app
bs-k8s-ceph
创建一个app rbd pool
# ceph osd pool create webapp
授权wordpress用户
# ceph auth get-or-create client.webapp mon 'allow r' osd 'allow class-read, allow rwx pool=webapp' -o ceph.client.webapp.keyring
# ceph auth get client.webapp
exported keyring for client.webapp
[client.webapp]
key = AQDDcnFeMcbnMxAA7hDGAmEAgpmrY8Z+ATFG+A==
caps mon = "allow r"
caps osd = "allow class-read, allow rwx pool=webapp" Mon 权限: 包括 r 、 w 、 x 。
OSD 权限: 包括 r 、 w 、 x 、 class-read 、 class-write
创建ceph secret
bs-k8s-master01 # ceph auth get-key client.admin | base64 #获取client.admin的keyring值，并用base64编码
QVFBdG1IQmVvdG5zTGhBQVFpa214WVNUZFdOcWVydGgyVVBlL0E9PQ==
# ceph auth get-key client.webapp | base64 #获取client.kube的keyring值，并用base64编码
QVFERGNuRmVNY2JuTXhBQTdoREdBbUVBZ3Btclk4WitBVEZHK0E9PQ==
# pwd
/data/k8s/app/wordpress
# cat namespace.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: namespace.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: v1
kind: Namespace
metadata:
name: myweb
labels:
name: myweb
# kubectl apply -f namespace.yaml
namespace/myweb created
# cat ceph-wordpress-secret.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: ceph-jenkins-secret.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: v1
kind: Secret
metadata:
name: ceph-admin-secret
namespace: myweb
data:
key: QVFBdG1IQmVvdG5zTGhBQVFpa214WVNUZFdOcWVydGgyVVBlL0E9PQ==
type: kubernetes.io/rbd
---
apiVersion: v1
kind: Secret
metadata:
name: ceph-myweb-secret
namespace: myweb
data:
key: QVFERGNuRmVNY2JuTXhBQTdoREdBbUVBZ3Btclk4WitBVEZHK0E9PQ==
type: kubernetes.io/rbd
# kubectl apply -f ceph-wordpress-secret.yaml
secret/ceph-admin-secret created
secret/ceph-myweb-secret created
使用StorageClass动态创建PV时，controller-manager会自动在Ceph上创建image，所以我们要为其准备好rbd命令。 如果集群是用kubeadm部署的，由于controller-manager官方镜像中没有rbd命令，所以我们要导入外部配置。
# cat external-storage-rbd-provisioner.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: external-storage-rbd-provisioner.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: v1
kind: ServiceAccount
metadata:
name: rbd-provisioner
namespace: myweb
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: rbd-provisioner
rules:
- apiGroups: [""]
resources: ["persistentvolumes"]
verbs: ["get", "list", "watch", "create", "delete"]
- apiGroups: [""]
resources: ["persistentvolumeclaims"]
verbs: ["get", "list", "watch", "update"]
- apiGroups: ["storage.k8s.io"]
resources: ["storageclasses"]
verbs: ["get", "list", "watch"]
- apiGroups: [""]
resources: ["events"]
verbs: ["create", "update", "patch"]
- apiGroups: [""]
resources: ["endpoints"]
verbs: ["get", "list", "watch", "create", "update", "patch"]
- apiGroups: [""]
resources: ["services"]
resourceNames: ["kube-dns"]
verbs: ["list", "get"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: rbd-provisioner
subjects:
- kind: ServiceAccount
name: rbd-provisioner
namespace: myweb
roleRef:
kind: ClusterRole
name: rbd-provisioner
apiGroup: rbac.authorization.k8s.io
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: rbd-provisioner
namespace: myweb
rules:
- apiGroups: [""]
resources: ["secrets"]
verbs: ["get"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: rbd-provisioner
namespace: myweb
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: rbd-provisioner
subjects:
- kind: ServiceAccount
name: rbd-provisioner
namespace: myweb
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: rbd-provisioner
namespace: myweb
spec:
replicas:
selector:
matchLabels:
app: rbd-provisioner
strategy:
type: Recreate
template:
metadata:
labels:
app: rbd-provisioner
spec:
containers:
- name: rbd-provisioner
image: "harbor.linux.com/rbd/rbd-provisioner:latest"
imagePullPolicy: IfNotPresent
env:
- name: PROVISIONER_NAME
value: ceph.com/rbd
imagePullSecrets:
- name: k8s-harbor-login
serviceAccount: rbd-provisioner
nodeSelector: ## 设置node筛选器，在特定label的节点上启动
rbd: "true"
节点打标签
#kubectl label nodes 20.0.0.204 rbd=true
# kubectl get nodes --show-labels
20.0.0.204 Ready node 46h v1.17.2 beta.kubernetes.io/arch=amd64,beta.kubernetes.io/os=linux,dashboard=true,kubernetes.io/arch=amd64,kubernetes.io/hostname=20.0.0.204,kubernetes.io/os=linux,kubernetes.io/role=node,metricsscraper=true,metricsserver=true,rbd=true
# kubectl apply -f external-storage-rbd-provisioner.yaml
serviceaccount/rbd-provisioner created
clusterrole.rbac.authorization.k8s.io/rbd-provisioner created
clusterrolebinding.rbac.authorization.k8s.io/rbd-provisioner created
role.rbac.authorization.k8s.io/rbd-provisioner created
rolebinding.rbac.authorization.k8s.io/rbd-provisioner created
deployment.apps/rbd-provisioner created
# kubectl get pods -n myweb -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
rbd-provisioner-9cf46c856-b9pm9 / Running 36s 172.20.46.83 20.0.0.204 <none> <none>
# cat ceph-wordpress-storageclass.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: ceph-jenkins-storageclass.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: ceph-wordpress
namespace: myweb
annotations:
storageclass.kubernetes.io/is-default-class: "false"
provisioner: ceph.com/rbd
reclaimPolicy: Retain
parameters:
monitors: 20.0.0.207:,20.0.0.208:,20.0.0.209:
adminId: admin
adminSecretName: ceph-admin-secret
adminSecretNamespace: myweb
pool: webapp
fsType: xfs
userId: webapp
userSecretName: ceph-myweb-secret
imageFormat: ""
imageFeatures: "layering"
# kubectl apply -f ceph-wordpress-storageclass.yaml
storageclass.storage.k8s.io/ceph-wordpress created
注: storageclass.kubernetes.io/is-default-class：注释为true，标记为默认的StorageClass，注释的任何其他值或缺失都被解释为false。 monitors：Ceph监视器，逗号分隔。此参数必需。 adminId：Ceph客户端ID，能够在pool中创建images。默认为“admin”。 adminSecretNamespace：adminSecret的namespace。默认为“default”。 adminSecret：adminId的secret。此参数必需。提供的secret必须具有“kubernetes.io/rbd”类型。 pool：Ceph RBD池。默认为“rbd”。 userId：Ceph客户端ID，用于映射RBD image。默认值与adminId相同。 userSecretName：用于userId映射RBD image的Ceph Secret的名称。它必须与PVC存在于同一namespace中。此参数必需。 fsType：kubernetes支持的fsType。默认值："ext4"。 imageFormat：Ceph RBD image格式，“1”或“2”。默认值为“1”。 imageFeatures：此参数是可选的，只有在设置imageFormat为“2”时才能使用。目前仅支持的功能为layering。默认为“”，并且未开启任何功能。 默认的StorageClass标记为(default)
创建pvc
动态卷配置的实现基于StorageClass API组中的API对象storage.k8s.io。
用户通过在其中包含存储类来请求动态调配存储PersistentVolumeClaim
# cat mysql-pvc.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: mysql-pvc.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mysql-pv-claim
namespace: myweb
labels:
app: wordpress
spec:
storageClassName: ceph-wordpress
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 2Gi
# cat wordpress-pvc.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: wordpress-pvc.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: wp-pv-claim
namespace: myweb
labels:
app: wordpress
spec:
storageClassName: ceph-wordpress
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 2Gi
# kubectl apply -f mysql-pvc.yaml
persistentvolumeclaim/mysql-pv-claim created
# kubectl apply -f wordpress-pvc.yaml
persistentvolumeclaim/wp-pv-claim created
# kubectl get pvc,pv -n myweb
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
persistentvolumeclaim/mysql-pv-claim Bound pvc-cc32b750-e602-4d8f-a054-a9941f971315 2Gi RWO ceph-wordpress 3m24s
persistentvolumeclaim/wp-pv-claim Bound pvc-113e27f5--4f90-80d6-b45cfcddca34 2Gi RWO ceph-wordpress 51s
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
persistentvolume/pvc-113e27f5--4f90-80d6-b45cfcddca34 2Gi RWO Retain Bound myweb/wp-pv-claim ceph-wordpress 50s
persistentvolume/pvc-cc32b750-e602-4d8f-a054-a9941f971315 2Gi RWO Retain Bound myweb/mysql-pv-claim ceph-wordpress 3m17s
可以看到已经实现了动态创建pv
使用持久卷部署WordPress和mysql
为mysql密码创建一个Secret,换命令行创建一次吧
# cat wordpress-mysql-password.sh
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: myweb-mysql-password.sh
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
##########################################################################
#!/bin/bash
kubectl -n myweb create secret generic mysql-pass --from-literal=password=zisefeizhu
# sh -x wordpress-mysql-password.sh
+ kubectl -n myweb create secret generic mysql-pass --from-literal=password=zisefeizhu
secret/mysql-pass created
准备资源清单
# cat mysql-deployment.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: mysql-deployment.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: v1
kind: Service
metadata:
name: wordpress-mysql
namespace: myweb
labels:
app: wordpress
spec:
ports:
- port:
selector:
app: wordpress
tier: mysql
clusterIP: None
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: wordpress-mysql
namespace: myweb
labels:
app: wordpress
spec:
selector:
matchLabels:
app: wordpress
tier: mysql
strategy:
type: Recreate
template:
metadata:
labels:
app: wordpress
tier: mysql
spec:
imagePullSecrets:
- name: k8s-harbor-login
containers:
- image: harbor.linux.com/myweb/mysql:5.6
name: mysql
env:
- name: MYSQL_ROOT_PASSWORD
valueFrom:
secretKeyRef:
name: mysql-pass
key: password
ports:
- containerPort:
name: mysql
volumeMounts:
- name: mysql-persistent-storage
mountPath: /var/lib/mysql
volumes:
- name: mysql-persistent-storage
persistentVolumeClaim:
claimName: mysql-pv-claim
nodeSelector: ## 设置node筛选器，在特定label的节点上启动
wordpress-mysql: "true" 节点打标签，按照规划是打到bs-k8s-node03节点上
# kubectl label nodes 20.0.0.206 wordpress-mysql=true
node/20.0.0.206 labeled
# kubectl apply -f mysql-deployment.yaml
service/wordpress-mysql created
deployment.apps/wordpress-mysql created
# kubectl get pods -n myweb -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
rbd-provisioner-9cf46c856-b9pm9 / Running 27m 172.20.46.83 20.0.0.204 <none> <none>
wordpress-mysql-6d7bd496b4-w4wlc / Running 4m39s 172.20.208.3 20.0.0.206 <none> <none>
mysql部署成功
# cat wordpress.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: wordpress.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: v1
kind: Service
metadata:
name: wordpress
namespace: myweb
labels:
app: wordpress
spec:
ports:
- port:
selector:
app: wordpress
tier: frontend
type: LoadBalancer
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: wordpress
namespace: myweb
labels:
app: wordpress
spec:
selector:
matchLabels:
app: wordpress
tier: frontend
strategy:
type: Recreate
template:
metadata:
labels:
app: wordpress
tier: frontend
spec:
imagePullSecrets:
- name: k8s-harbor-login
containers:
- image: harbor.linux.com/myweb/wordpress:4.8
name: wordpress
env:
- name: WORDPRESS_DB_HOST
value: wordpress-mysql
- name: WORDPRESS_DB_PASSWORD
valueFrom:
secretKeyRef:
name: mysql-pass
key: password
ports:
- containerPort:
name: wordpress
volumeMounts:
- name: wordpress-persistent-storage
mountPath: /var/www/html
volumes:
- name: wordpress-persistent-storage
persistentVolumeClaim:
claimName: wp-pv-claim
nodeSelector: ## 设置node筛选器，在特定label的节点上启动
wordpress-wordpress: "true"
# kubectl apply -f wordpress.yaml
service/wordpress created
deployment.apps/wordpress created
# kubectl get pods -n myweb -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
rbd-provisioner-9cf46c856-b9pm9 / Running 59m 172.20.46.83 20.0.0.204 <none> <none>
wordpress-6677ff7bd-sc45d / Running 10m 172.20.208.18 20.0.0.206 <none> <none>
wordpress-mysql-6d7bd496b4-w4wlc / Running 36m 172.20.208.10 20.0.0.206 <none> <none>
部署代理
# cat wordpress-ingressroute.yaml
##########################################################################
#Author: zisefeizhu
#QQ: ********
#Date: --
#FileName: myweb--ingressroute.yaml
#URL: https://www.cnblogs.com/zisefeizhu/
#Description: The test script
#Copyright (C): All rights reserved
###########################################################################
apiVersion: traefik.containo.us/v1alpha1
kind: IngressRoute
metadata:
name: wordpress
namespace: myweb
spec:
entryPoints:
- web
routes:
- match: Host(`wordpress.linux.com`)
kind: Rule
services:
- name: wordpress
port:
# kubectl apply -f wordpress-ingressroute.yaml
ingressroute.traefik.containo.us/wordpress created
代理成功
看样子是OK了，按照步骤next吧
测试
思路：删除mysql-deployment.yaml 即只保留mysql pvc 然后重启mysql-deployment.yaml，web访问看能否成功。
# kubectl delete -f mysql-deployment.yaml
service "wordpress-mysql" deleted
deployment.apps "wordpress-mysql" deleted
# kubectl get pvc -n myweb
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
mysql-pv-claim Bound pvc-cc32b750-e602-4d8f-a054-a9941f971315 2Gi RWO ceph-wordpress 63m
wp-pv-claim Bound pvc-113e27f5--4f90-80d6-b45cfcddca34 2Gi RWO ceph-wordpress 61m
# kubectl apply -f mysql-deployment.yaml
service/wordpress-mysql created
deployment.apps/wordpress-mysql created
# kubectl get pods -n myweb
NAME READY STATUS RESTARTS AGE
rbd-provisioner-9cf46c856-b9pm9 / Running 71m
wordpress-6677ff7bd-sc45d / Running 22m
wordpress-mysql-6d7bd496b4-62dps / Running 18s
ok了。这样，当我们的集群负载过高的时候就可以先把pod给停了 ，只保留pvc即可。
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