kubernetes存储（三）——K8S的Volumes配置管理（动态卷+StorageClass存储类（class）+部署mysql主从集群）
文章目录
- 1.StorageClass介绍
- 2.配置NFS Client Provisioner
- 3.StatefulSe控制器
- 3.1 通过无头服务创建StatefulSe控制器维持Pod的拓扑状态
- 3.2 StatefulSet的应用状态与弹缩
- 3.3 StatefulSet+存储
- 3.4 使用statefullset部署mysql主从集群
1.StorageClass介绍
StorageClass提供了一种描述存储类（class）的方法，不同的class可能会映射到不同的服务质量等级和备份策略或其他策略等。
每个 StorageClass 都包含 provisioner、parameters 和 reclaimPolicy 字段， 这些字段会在 StorageClass需要动态分配 PersistentVolume 时会使用到。
StorageClass的属性
• Provisioner（存储分配器）：用来决定使用哪个卷插件分配 PV，该字段必须指定。可以指 定内部分配器，也可以指定外部分配器。外部分配器的代码地址为： kubernetesincubator/external-storage，其中包括NFS和Ceph等。
• Reclaim Policy（回收策略）：通过reclaimPolicy字段指定创建的Persistent Volume的回收 策略，回收策略包括：Delete 或者 Retain，没有指定默认为Delete。
• 更多属性查看：https://kubernetes.io/zh/docs/concepts/storage/storage-classes/
2.配置NFS Client Provisioner
NFS Client Provisioner是一个automatic provisioner，使用NFS作为存储，自动创建PV和对应的 PVC，本身不提供NFS存储，需要外部先有一套NFS存储服务。
• PV以 ${namespace}-${pvcName}-${pvName}的命名格式提供（在NFS服务器上）
• PV回收的时候以 archieved-${namespace}-${pvcName}-${pvName} 的命名格式（在NFS 服务器上）
nfs-client-provisioner源码地址：https://github.com/kubernetes-incubator/external-storage/tree/master/nfs-client/deploy
[root@harbor ~]# vim /etc/exports
[root@harbor ~]# cat /etc/exports
/nfsdata *(rw,sync,no_root_squash)
[root@harbor ~]# exportfs -rv
exporting *:/nfsdata
[root@harbor ~]# showmount -e
Export list for harbor:
/nfsdata *
[kubeadm@server1 ~]$ cd vol/
[kubeadm@server1 vol]$ mkdir nfs-client
[kubeadm@server1 vol]$ cd nfs-client/
[kubeadm@server1 nfs-client]$ vim rbac.yml ##添加角色绑定的名称空间
apiVersion: v1
kind: ServiceAccount
metadata:
name: nfs-client-provisioner
# replace with namespace where provisioner is deployed
namespace: default
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: nfs-client-provisioner-runner
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"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: run-nfs-client-provisioner
subjects:
- kind: ServiceAccount
name: nfs-client-provisioner
# replace with namespace where provisioner is deployed
namespace: default
roleRef:
kind: ClusterRole
name: nfs-client-provisioner-runner
apiGroup: rbac.authorization.k8s.io
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: leader-locking-nfs-client-provisioner
# replace with namespace where provisioner is deployed
namespace: default
rules:
- apiGroups: [""]
resources: ["endpoints"]
verbs: ["get", "list", "watch", "create", "update", "patch"]
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: leader-locking-nfs-client-provisioner
# replace with namespace where provisioner is deployed
namespace: default
subjects:
- kind: ServiceAccount
# replace with namespace where provisioner is deployed
namespace: default
roleRef:
kind: Role
name: leader-locking-nfs-client-provisioner
apiGroup: rbac.authorization.k8s.io[kubeadm@server1 nfs-client]$ vim deployment.yml ##删除重复的选择器字段
apiVersion: apps/v1
kind: Deployment
metadata:
name: nfs-client-provisioner
labels:
app: nfs-client-provisioner
# replace with namespace where provisioner is deployed
namespace: default
spec:
replicas: 1
strategy:
type: Recreate
selector:
matchLabels:
app: nfs-client-provisioner
template:
metadata:
labels:
app: nfs-client-provisioner
spec:
serviceAccountName: nfs-client-provisioner
containers:
- name: nfs-client-provisioner
image: nfs-client-provisioner:latest ##镜像需要下载并上传到仓库
volumeMounts:
- name: nfs-client-root
mountPath: /persistentvolumes
env:
- name: PROVISIONER_NAME
value: red.org/nfs
- name: NFS_SERVER
value: 172.25.1.11
- name: NFS_PATH
value: /nfsdata
volumes:
- name: nfs-client-root
nfs:
server: 172.25.1.11
path: /nfsdata
[kubeadm@server1 nfs-client]$ vim class.yml ##创建存储类
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: managed-nfs-storage
provisioner: red.org/nfs
parameters:
archiveOnDelete: "false"
[kubeadm@server1 nfs-client]$ vim pvc.yml ##创建pvc
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: pvc1
annotations:
volume.beta.kubernetes.io/storage-class: "managed-nfs-storage"
spec:
accessModes:
- ReadWriteMany
resources:
requests:
storage: 100Mi[kubeadm@server1 nfs-client]$ vim pod.yml
kind: Pod
apiVersion: v1
metadata:
name: test-pod
spec:
containers:
- name: test-pod
image: busybox
command:
- "/bin/sh"
args:
- "-c"
- "touch /mnt/SUCCESS && exit 0 || exit 1"
volumeMounts:
- name: nfs-pvc
mountPath: "/mnt"
restartPolicy: "Never"
volumes:
- name: nfs-pvc
persistentVolumeClaim:
claimName: pvc1 
再次改为false
以上为动态卷的存储方式
默认的 StorageClass 将被用于动态的为没有特定 storage class 需求的 PersistentVolumeClaims 配置存储：（只能有一个默认StorageClass）
如果没有默认StorageClass，PVC 也没有指定storageClassName 的值，那么意味着它只能够跟 storageClassName 也是“”的 PV 进行绑定。
[kubeadm@server1 nfs-client]$ kubectl get pvc
No resources found in default namespace.
[kubeadm@server1 nfs-client]$ kubectl get pv
No resources found in default namespace.
[kubeadm@server1 nfs-client]$ kubectl get storageclasses.storage.k8s.io
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
managed-nfs-storage red.org/nfs Delete Immediate false 6m33s
[kubeadm@server1 nfs-client]$ kubectl patch storageclass managed-nfs-storage -p '{"metadata":{"annotations":{"storageclass.kubernetes.io/is-default-class":"true"}}}'
storageclass.storage.k8s.io/managed-nfs-storage patched
[kubeadm@server1 nfs-client]$ kubectl get storageclasses.storage.k8s.io
NAME PROVISIONER RECLAIMPOLICY VOLUMEBINDINGMODE ALLOWVOLUMEEXPANSION AGE
managed-nfs-storage (default) red.org/nfs Delete Immediate false 6m47s
这个时候不用指定存储类也可以绑定
[kubeadm@server1 nfs-client]$ vim pvc.yml
[kubeadm@server1 nfs-client]$ cat pvc.yml
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: pvc1
# annotations:
# volume.beta.kubernetes.io/storage-class: "managed-nfs-storage"
spec:
accessModes:
- ReadWriteMany
resources:
requests:
storage: 1Gi
[kubeadm@server1 nfs-client]$ kubectl apply -f pvc.yml
persistentvolumeclaim/pvc1 created
[kubeadm@server1 nfs-client]$ kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
pvc1 Bound pvc-b67fda47-02d6-44f6-bd7d-d22a90369721 1Gi RWX managed-nfs-storage 12s
3.StatefulSe控制器
3.1 通过无头服务创建StatefulSe控制器维持Pod的拓扑状态
创建service
[kubeadm@server1 nginx]$ pwd
/home/kubeadm/vol/nginx
[kubeadm@server1 nginx]$ vim service.yml
[kubeadm@server1 nginx]$ cat service.yml
apiVersion: v1
kind: Service
metadata:
name: nginx
labels:
app: nginx
spec:
ports:
- port: 80
name: web
clusterIP: None
selector:
app: nginx
[kubeadm@server1 nginx]$ kubectl apply -f service.yml
service/nginx created
[kubeadm@server1 nginx]$ kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.96.0.1 <none> 443/TCP 13d
nginx ClusterIP None <none> 80/TCP 3s
创建statefulset控制器
[kubeadm@server1 nginx]$ vim statefulset.yml
[kubeadm@server1 nginx]$ cat statefulset.yml
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: web
spec:
serviceName: "nginx"
replicas: 2
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
[kubeadm@server1 nginx]$ kubectl apply -f statefulset.yml
statefulset.apps/web created
[kubeadm@server1 nginx]$ kubectl get pod
NAME READY STATUS RESTARTS AGE
nfs-client-provisioner-96649cd96-gvzch 1/1 Running 0 54m
web-0 1/1 Running 0 18s
web-1 1/1 Running 0 17s
[kubeadm@server1 nginx]$ vim /etc/resolv.conf
[kubeadm@server1 nginx]$ cat /etc/resolv.conf
nameserver 10.96.0.10
nameserver 114.114.114.114
[kubeadm@server1 nginx]$ kubectl describe svc nginx
Name: nginx
Namespace: default
Labels: app=nginx
Annotations: Selector: app=nginx
Type: ClusterIP
IP: None
Port: web 80/TCP
TargetPort: 80/TCP
Endpoints: 10.244.1.87:80,10.244.2.104:80
Session Affinity: None
Events: <none>
[kubeadm@server1 nginx]$ dig nginx.default.svc.cluster.local
; <<>> DiG 9.9.4-RedHat-9.9.4-72.el7 <<>> nginx.default.svc.cluster.local
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 41306
;; flags: qr aa rd; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;nginx.default.svc.cluster.local. IN A
;; ANSWER SECTION:
nginx.default.svc.cluster.local. 30 IN A 10.244.2.104
nginx.default.svc.cluster.local. 30 IN A 10.244.1.87
;; Query time: 0 msec
;; SERVER: 10.96.0.10#53(10.96.0.10)
;; WHEN: Thu Jul 02 16:11:09 CST 2020
;; MSG SIZE rcvd: 154
3.2 StatefulSet的应用状态与弹缩
StatefulSet将应用状态抽象成了两种情况：
• 拓扑状态：应用实例必须按照某种顺序启动。新创建的Pod必须和原来Pod的网络标识一样
• 存储状态：应用的多个实例分别绑定了不同存储数据。
StatefulSet给所有的Pod进行了编号，编号规则是：$(statefulset名称)-$(序号)，从0开始。
Pod被删除后重建，重建Pod的网络标识也不会改变,Pod的拓扑状态按照Pod的“名字+编号”的方 式固定下来,并且为每个Pod提供了一个固定且唯一的访问入口,即Pod对应的DNS记录。
kubectl 弹缩
首先,想要弹缩的StatefulSet. 需先清楚是否能弹缩该应用.
kubectl get statefulsets •
改变StatefulSet副本数量: • $ kubectl scale statefulsets --replicas=
• 如果StatefulSet开始由 kubectl apply 或 kubectl create --save-config 创建,更新StatefulSet manifests中的 .spec.replicas, 然后执行命令 kubectl apply: • $ kubectl apply -f
• 也可以通过命令 kubectl edit 编辑该字段: • $ kubectl edit statefulsets
• 使用 kubectl patch: • $ kubectl patch statefulsets -p '{“spec”:{“replicas”:}}'
3.3 StatefulSet+存储
PV和PVC的设计，使得StatefulSet对存储状态的管理成为了可能:
Pod的创建也是严格按照编号顺序进行的。比如在web-0进入到running状态，并且Conditions为 Ready之前，web-1一直会处于pending状态。
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: web
spec:
serviceName: "nginx"
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
volumeMounts:
- name: www
mountPath: /usr/share/nginx/html
volumeClaimTemplates:
- metadata:
name: www
spec:
storageClassName: managed-nfs-storage
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
StatefulSet还会为每一个Pod分配并创建一个同样编号的PVC。这样，kubernetes就可以通过 Persistent Volume机制为这个PVC绑定对应的PV，从而保证每一个Pod都拥有一个独立的 Volume。
设置负载均衡
[root@harbor ~]# cd /nfsdata/
[root@harbor nfsdata]# ls
default-www-web-0-pvc-6afe237f-9c4c-42d3-a337-3d78abd3e44a
default-www-web-1-pvc-ee23b027-e71c-43ef-bd87-d156db85397d
default-www-web-2-pvc-d8e5aebd-e248-4039-8992-f7e147b7d430
[root@harbor nfsdata]# cd default-www-web-0-pvc-6afe237f-9c4c-42d3-a337-3d78abd3e44a/
[root@harbor default-www-web-0-pvc-6afe237f-9c4c-42d3-a337-3d78abd3e44a]# echo web-0 > index.html
[root@harbor default-www-web-0-pvc-6afe237f-9c4c-42d3-a337-3d78abd3e44a]# cd ..
[root@harbor nfsdata]# cd default-www-web-1-pvc-ee23b027-e71c-43ef-bd87-d156db85397d/
[root@harbor default-www-web-1-pvc-ee23b027-e71c-43ef-bd87-d156db85397d]# echo web-1 > index.html
[root@harbor default-www-web-1-pvc-ee23b027-e71c-43ef-bd87-d156db85397d]# cd ..
[root@harbor nfsdata]# cd default-www-web-2-pvc-d8e5aebd-e248-4039-8992-f7e147b7d430/
[root@harbor default-www-web-2-pvc-d8e5aebd-e248-4039-8992-f7e147b7d430]# echo web-2 > index.html
再次拉伸回使用原先的标识符
3.4 使用statefullset部署mysql主从集群
参考官网：https://kubernetes.io/zh/docs/tasks/run-application/run-replicated-stateful-application/
创建configmap配置文件
这个 ConfigMap 提供 my.cnf 覆盖，使可以独立控制 MySQL 主服务器和从服务器的配置。
[kubeadm@server1 mysql]$ cat cm.yml
apiVersion: v1
kind: ConfigMap
metadata:
name: mysql
labels:
app: mysql
data:
master.cnf: |
# Apply this config only on the master.
[mysqld]
log-bin
slave.cnf: |
# Apply this config only on slaves.
[mysqld]
super-read-only
[kubeadm@server1 mysql]$ vim cm.yml
[kubeadm@server1 mysql]$ kubectl apply -f cm.yml
configmap/mysql created
[kubeadm@server1 mysql]$ kubectl get cm.
NAME DATA AGE
my-config 2 4d21h
my-config-2 1 4d21h
my-config-3 2 4d21h
mysql 2 6s
nginx-config 1 4d10h
创建service
Headless Service 给 StatefulSet 控制器为集合中每个 Pod 创建的 DNS 条目提供了一个宿主。因为 Headless Service 名为 mysql，所以可以通过在同一 Kubernetes 集群和 namespace 中的任何其他 Pod 内解析 .mysql 来访问 Pod。
客户端 Service 称为 mysql-read，是一种常规 Service，具有其自己的群集 IP，该群集 IP 在报告为就绪的所有MySQL Pod 中分配连接。可能端点的集合包括 MySQL 主节点和所有从节点。
请注意，只有读取查询才能使用负载平衡的客户端 Service。因为只有一个 MySQL 主服务器，所以客户端应直接连接到 MySQL 主服务器 Pod (通过其在 Headless Service 中的 DNS 条目)以执行写入操作。
[kubeadm@server1 mysql]$ cat service.yml
apiVersion: v1
kind: Service
metadata:
name: mysql
labels:
app: mysql
spec:
ports:
- name: mysql
port: 3306
clusterIP: None
selector:
app: mysql
---
# Client service for connecting to any MySQL instance for reads.
# For writes, you must instead connect to the master: mysql-0.mysql.
apiVersion: v1
kind: Service
metadata:
name: mysql-read
labels:
app: mysql
spec:
ports:
- name: mysql
port: 3306
selector:
app: mysql
创建statefulset
[root@server2 mysql]# cat statefulset.yml
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: mysql
spec:
selector:
matchLabels:
app: mysql
serviceName: mysql
replicas: 3
template:
metadata:
labels:
app: mysql
spec:
initContainers:
- name: init-mysql
image: mysql:5.7
command:
- bash
- "-c"
- |
set -ex
# Generate mysql server-id from pod ordinal index.
[[ `hostname` =~ -([0-9]+)$ ]] || exit 1
ordinal=${BASH_REMATCH[1]}
echo [mysqld] > /mnt/conf.d/server-id.cnf
# Add an offset to avoid reserved server-id=0 value.
echo server-id=$((100 + $ordinal)) >> /mnt/conf.d/server-id.cnf
# Copy appropriate conf.d files from config-map to emptyDir.
if [[ $ordinal -eq 0 ]]; then
cp /mnt/config-map/master.cnf /mnt/conf.d/
else
cp /mnt/config-map/slave.cnf /mnt/conf.d/
fi
volumeMounts:
- name: conf
mountPath: /mnt/conf.d
- name: config-map
mountPath: /mnt/config-map
- name: clone-mysql
image: xtrabackup:1.0
command:
- bash
- "-c"
- |
set -ex
# Skip the clone if data already exists.
[[ -d /var/lib/mysql/mysql ]] && exit 0
# Skip the clone on master (ordinal index 0).
[[ `hostname` =~ -([0-9]+)$ ]] || exit 1
ordinal=${BASH_REMATCH[1]}
[[ $ordinal -eq 0 ]] && exit 0
# Clone data from previous peer.
ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql
# Prepare the backup.
xtrabackup --prepare --target-dir=/var/lib/mysql
volumeMounts:
- name: data
mountPath: /var/lib/mysql
subPath: mysql
- name: conf
mountPath: /etc/mysql/conf.d
containers:
- name: mysql
image: mysql:5.7
env:
- name: MYSQL_ALLOW_EMPTY_PASSWORD
value: "1"
ports:
- name: mysql
containerPort: 3306
volumeMounts:
- name: data
mountPath: /var/lib/mysql
subPath: mysql
- name: conf
mountPath: /etc/mysql/conf.d
resources:
requests:
cpu: 500m
memory: 512M
livenessProbe:
exec:
command: ["mysqladmin", "ping"]
initialDelaySeconds: 30
periodSeconds: 10
timeoutSeconds: 5
readinessProbe:
exec:
# Check we can execute queries over TCP (skip-networking is off).
command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"]
initialDelaySeconds: 5
periodSeconds: 2
timeoutSeconds: 1
- name: xtrabackup
image: xtrabackup:1.0 ##用于打开3307端口，向slave发送数据
ports:
- name: xtrabackup
containerPort: 3307
command:
- bash
- "-c"
- |
set -ex
cd /var/lib/mysql
# Determine binlog position of cloned data, if any.
if [[ -f xtrabackup_slave_info && "x$(<xtrabackup_slave_info)" != "x" ]]; then
# XtraBackup already generated a partial "CHANGE MASTER TO" query
# because we're cloning from an existing slave. (Need to remove the tailing semicolon!)
cat xtrabackup_slave_info | sed -E 's/;$//g' > change_master_to.sql.in
# Ignore xtrabackup_binlog_info in this case (it's useless).
rm -f xtrabackup_slave_info xtrabackup_binlog_info
elif [[ -f xtrabackup_binlog_info ]]; then
# We're cloning directly from master. Parse binlog position.
[[ `cat xtrabackup_binlog_info` =~ ^(.*?)[[:space:]]+(.*?)$ ]] || exit 1
rm -f xtrabackup_binlog_info xtrabackup_slave_info
echo "CHANGE MASTER TO MASTER_LOG_FILE='${BASH_REMATCH[1]}',\
MASTER_LOG_POS=${BASH_REMATCH[2]}" > change_master_to.sql.in
fi
# Check if we need to complete a clone by starting replication.
if [[ -f change_master_to.sql.in ]]; then
echo "Waiting for mysqld to be ready (accepting connections)"
until mysql -h 127.0.0.1 -e "SELECT 1"; do sleep 1; done
echo "Initializing replication from clone position"
mysql -h 127.0.0.1 \
-e "$(<change_master_to.sql.in), \
MASTER_HOST='mysql-0.mysql', \
MASTER_USER='root', \
MASTER_PASSWORD='', \
MASTER_CONNECT_RETRY=10; \
START SLAVE;" || exit 1
# In case of container restart, attempt this at-most-once.
mv change_master_to.sql.in change_master_to.sql.orig
fi
# Start a server to send backups when requested by peers.
exec ncat --listen --keep-open --send-only --max-conns=1 3307 -c \
"xtrabackup --backup --slave-info --stream=xbstream --host=127.0.0.1 --user=root"
volumeMounts:
- name: data
mountPath: /var/lib/mysql
subPath: mysql
- name: conf
mountPath: /etc/mysql/conf.d
resources:
requests:
cpu: 100m
memory: 100Mi
volumes:
- name: conf
emptyDir: {}
- name: config-map
configMap:
name: mysql
volumeClaimTemplates:
- metadata:
name: data
spec:
accessModes: ["ReadWriteOnce"]
resources:
requests:
storage: 10Gi 
[kubeadm@server1 mysql]$ kubectl logs mysql-0 -c init-mysql
++ hostname
+ [[ mysql-0 =~ -([0-9]+)$ ]]
+ ordinal=0
+ echo '[mysqld]'
+ echo server-id=100
+ [[ 0 -eq 0 ]]
+ cp /mnt/config-map/master.cnf /mnt/conf.d/
[kubeadm@server1 mysql]$ kubectl logs mysql-0 -c clone-mysql
+ [[ -d /var/lib/mysql/mysql ]]
+ exit 0
[kubeadm@server1 mysql]$ kubectl logs mysql-1 -c clone-mysql
+ [[ -d /var/lib/mysql/mysql ]]
+ exit 0
[kubeadm@server1 mysql]$ kubectl logs mysql-2 -c clone-mysql
+ [[ -d /var/lib/mysql/mysql ]]
++ hostname
+ [[ mysql-2 =~ -([0-9]+)$ ]]
+ ordinal=2
+ [[ 2 -eq 0 ]]
+ ncat --recv-only mysql-1.mysql 3307
+ xbstream -x -C /var/lib/mysql
+ xtrabackup --prepare --target-dir=/var/lib/mysql
salve1复制master数据，slave2复制slave1的数据
[kubeadm@server1 mysql]$ kubectl exec mysql-0 -c mysql -- ls /etc/mysql/conf.d
master.cnf
server-id.cnf
[kubeadm@server1 mysql]$ kubectl exec mysql-0 -c mysql -- cat /etc/mysql/conf.d/master.cnf
# Apply this config only on the master.
[mysqld]
log-bin
[kubeadm@server1 mysql]$ kubectl exec mysql-0 -c mysql -- cat /etc/mysql/conf.d/server-id.cnf
[mysqld]
server-id=100
测试主从复制
[kubeadm@server1 mysql]$ mysql -h mysql-0.mysql.default.svc.cluster.local
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MySQL connection id is 429
Server version: 5.7.30-log MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MySQL [(none)]> show databases;
+------------------------+
| Database |
+------------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| xtrabackup_backupfiles |
+------------------------+
5 rows in set (0.02 sec)
MySQL [(none)]> create database test;
Query OK, 1 row affected (0.01 sec)
MySQL [(none)]> Bye
[kubeadm@server1 mysql]$ mysql -h mysql-1.mysql.default.svc.cluster.local
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MySQL connection id is 455
Server version: 5.7.30 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MySQL [(none)]> show databases;
+------------------------+
| Database |
+------------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
| xtrabackup_backupfiles |
+------------------------+
6 rows in set (0.03 sec)
MySQL [(none)]> Bye
[kubeadm@server1 mysql]$ mysql -h mysql-2.mysql.default.svc.cluster.local
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MySQL connection id is 453
Server version: 5.7.30 MySQL Community Server (GPL)
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MySQL [(none)]> show databases;
+------------------------+
| Database |
+------------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test |
| xtrabackup_backupfiles |
+------------------------+
6 rows in set (0.01 sec)
MySQL [(none)]> Bye
