案例(部署mysql)本节使用 StatefulSet 控制器部署一个 MySQL 集群，然后进行宕机测试，观察集群是否可以正常恢复使用并且不丢失数据。
实现的集群有如下特征：
是一个主从复制的 MySQL 集群
1个主节点， 多个从节点
从节点能够水平扩展
所有的写操作，只能在主节点上执行
读操作可以在所有节点上执行
#准备xtrabackup镜像
[root@localhost7C mysql]# docker pull registry.cn-hangzhou.aliyuncs.com/hxpdocker/xtrabackup:1.0
[root@localhost7C mysql]# docker tag c415dbd7af07 harobr.zzhz.com/linux39/xtrabackup:1.0
[root@localhost7C mysql]# docker push harobr.zzhz.com/linux39/xtrabackup:1.0
#准备mysql 镜像
[root@localhost7C mysql]# docker pull registry.cn-hangzhou.aliyuncs.com/acs-sample/mysql:5.7
[root@localhost7C mysql]# docker tag 54fec2fa59d0 harobr.zzhz.com/linux39/mysql:5.7
[root@localhost7C mysql]# docker push harobr.zzhz.com/linux39/mysql:5.7
2.安装nfs服务器，基于PV作为后端存储 [root@localhost7B ]# cat /etc/exports /data/k8sdata *(rw,no_root_squash) [root@localhost7B ~]# mkdir /data/k8sdata/magedu/mysql-datadir-1 [root@localhost7B ~]# mkdir /data/k8sdata/magedu/mysql-datadir-2 [root@localhost7B ~]# mkdir /data/k8sdata/magedu/mysql-datadir-3 [root@localhost7B ~]# mkdir /data/k8sdata/magedu/mysql-datadir-4 [root@localhost7B ]# systemctl restart nfs-server.service
[root@localhost7C mysql]# tree
├── mysql-configmap.yaml
├── mysql-services.yaml
├── mysql-statefulset.yaml
└── pv
└── mysql-persistentvolume.yaml
[root@localhost7C mysql]# cat pv/mysql-persistentvolume.yaml --- apiVersion: v1 kind: PersistentVolume metadata: name: mysql-datadir-1 namespace: magedu spec: capacity: storage: 50Gi accessModes: - ReadWriteOnce nfs: path: /data/k8sdata/magedu/mysql-datadir-1 server: 192.168.80.110 --- apiVersion: v1 kind: PersistentVolume metadata: name: mysql-datadir-2 namespace: magedu spec: capacity: storage: 50Gi accessModes: - ReadWriteOnce nfs: path: /data/k8sdata/magedu/mysql-datadir-2 server: 192.168.80.110 --- apiVersion: v1 kind: PersistentVolume metadata: name: mysql-datadir-3 namespace: magedu spec: capacity: storage: 50Gi accessModes: - ReadWriteOnce nfs: path: /data/k8sdata/magedu/mysql-datadir-3 server: 192.168.80.110 --- apiVersion: v1 kind: PersistentVolume metadata: name: mysql-datadir-4 namespace: magedu spec: capacity: storage: 50Gi accessModes: - ReadWriteOnce nfs: path: /data/k8sdata/magedu/mysql-datadir-4 server: 192.168.80.110
#mysql主从的配置文件
[root@localhost7C mysql]# cat mysql-configmap.yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: mysql
labels:
app: mysql
data:
master.cnf: |
# Apply this config only on the master.
[mysqld]
log-bin
log_bin_trust_function_creators=1
lower_case_table_names=1
slave.cnf: |
# Apply this config only on slaves.
[mysqld]
super-read-only
log_bin_trust_function_creators=1
@两个 Service
[root@localhost7C mysql]# cat mysql-services.yaml
# StatefulSet成员的稳定DNS项的无头服务。
apiVersion: v1
kind: Service
metadata:
name: mysql
labels:
app: mysql
spec:
ports:
- name: mysql
port: 3306
clusterIP: None
selector:
app: mysql
---
#用于连接到任何MySQL实例进行读取的客户端服务。
#对于写入，您必须连接到master：mysql-0.mysql。
apiVersion: v1
kind: Service
metadata:
name: mysql-read
labels:
app: mysql
spec:
# type: NodePort
ports:
- name: mysql
port: 3306
# targetPort: 3306
# nodePort: 33306
selector:
app: mysql
#yaml清单
[root@localhost7C mysql]# cat mysql-statefulset.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: mysql
spec:
selector:
matchLabels:
app: mysql
serviceName: mysql
replicas: 2
template:
metadata:
labels:
app: mysql
spec:
#定义初始化容器
initContainers:
- name: init-mysql
image: harbor.zzhz.com/linux39/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 [[ $ordinal -eq 0 ]]; then
cp /mnt/config-map/master.cnf /mnt/conf.d/
else
cp /mnt/config-map/slave.cnf /mnt/conf.d/
fi
volumeMounts:
- name: conf #调用emptyDir
mountPath: /mnt/conf.d
- name: config-map #调用configmap
mountPath: /mnt/config-map
#定义初始化容器
- name: clone-mysql
image: harbor.zzhz.com/linux39/xtrabackup:1.0
command:
- bash
- "-c"
- |
set -ex
# Skip the clone if data already exists.
[[ -d /var/lib/mysql/mysql ]] && exit 0
# Skip the clone on master (ordinal index 0).
[[ `hostname` =~ -([0-9]+)$ ]] || exit 1
ordinal=${BASH_REMATCH[1]}
[[ $ordinal -eq 0 ]] && exit 0
# Clone data from previous peer.
ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql
# Prepare the backup.
xtrabackup --prepare --target-dir=/var/lib/mysql
volumeMounts:
- name: data #调用PVC模版
mountPath: /var/lib/mysql
subPath: mysql
- name: conf #调用emptyDir
mountPath: /etc/mysql/conf.d
#定义容器
containers:
- name: mysql
image: harbor.zzhz.com/linux39/mysql:5.7
env:
- name: MYSQL_ALLOW_EMPTY_PASSWORD
value: "1"
ports:
- name: mysql
containerPort: 3306
volumeMounts:
- name: data #调用PVC模版
mountPath: /var/lib/mysql
subPath: mysql
- name: conf #调用emptyDir
mountPath: /etc/mysql/conf.d
resources:
requests:
cpu: 500m
memory: 1Gi
livenessProbe:
exec:
command: ["mysqladmin", "ping"]
initialDelaySeconds: 30
periodSeconds: 10
timeoutSeconds: 5
readinessProbe:
exec:
# Check we can execute queries over TCP (skip-networking is off).
command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"]
initialDelaySeconds: 5
periodSeconds: 2
timeoutSeconds: 1
#定义容器
- name: xtrabackup
image: harbor.zzhz.com/linux39/xtrabackup:1.0
ports:
- name: xtrabackup
containerPort: 3307
command:
- bash
- "-c"
- |
set -ex
cd /var/lib/mysql
# Determine binlog position of cloned data, if any.
if [[ -f xtrabackup_slave_info ]]; then
# XtraBackup already generated a partial "CHANGE MASTER TO" query
# because we're cloning from an existing slave.
mv xtrabackup_slave_info change_master_to.sql.in
# Ignore xtrabackup_binlog_info in this case (it's useless).
rm -f xtrabackup_binlog_info
elif [[ -f xtrabackup_binlog_info ]]; then
# We're cloning directly from master. Parse binlog position.
[[ `cat xtrabackup_binlog_info` =~ ^(.*?)[[:space:]]+(.*?)$ ]] || exit 1
rm xtrabackup_binlog_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"
# In case of container restart, attempt this at-most-once.
mv change_master_to.sql.in change_master_to.sql.orig
mysql -h 127.0.0.1 <<EOF
$(<change_master_to.sql.orig),
MASTER_HOST='mysql-0.mysql',
MASTER_USER='root',
MASTER_PASSWORD='',
MASTER_CONNECT_RETRY=10;
START SLAVE;
EOF
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 #调用PVC模版
mountPath: /var/lib/mysql
subPath: mysql
- name: conf #调用emptyDir
mountPath: /etc/mysql/conf.d
resources:
requests:
cpu: 100m
memory: 100Mi
volumes:
- name: conf #定义和启用emptyDir
emptyDir: {}
- name: config-map #定义configmap
configMap:
name: mysql
volumeClaimTemplates: #定义PVC模版,
- metadata:
name: data #PVC模版名称：PVC名称==PVC模版名称+pod名：如下面的data-mysql-0
spec:
accessModes: ["ReadWriteOnce"]
resources:
requests:
storage: 10Gi
#查看sc，pv，pvc，pod，statefulset，svc
[root@localhost7C mysql]# kubectl get pv,pvc,pod,svc,statefulsets -A -o wide
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE VOLUMEMODE
persistentvolume/mysql-datadir-1 50Gi RWO Retain Bound default/data-mysql-0 140m Filesystem
persistentvolume/mysql-datadir-2 50Gi RWO Retain Bound default/data-mysql-1 140m Filesystem
persistentvolume/mysql-datadir-3 50Gi RWO Retain Available 140m Filesystem
persistentvolume/mysql-datadir-4 50Gi RWO Retain Bound default/data-mysql-2 140m Filesystem
NAMESPACE NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE VOLUMEMODE
default persistentvolumeclaim/data-mysql-0 Bound mysql-datadir-1 50Gi RWO 84m Filesystem
default persistentvolumeclaim/data-mysql-1 Bound mysql-datadir-2 50Gi RWO 77m Filesystem
default persistentvolumeclaim/data-mysql-2 Bound mysql-datadir-4 50Gi RWO 74m Filesystem
NAMESPACE NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
default pod/mysql-0 2/2 Running 0 30m 10.20.4.54 192.168.80.170 <none> <none>
default pod/mysql-1 2/2 Running 1 77m 10.20.5.50 192.168.80.160 <none> <none>
NAMESPACE NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
default service/mysql ClusterIP None <none> 3306/TCP 138m app=mysql
default service/mysql-read ClusterIP 10.10.124.250 <none> 3306/TCP 138m app=mysql
NAMESPACE NAME READY AGE CONTAINERS IMAGES
default statefulset.apps/mysql 2/2 79m mysql,xtrabackup harbor.zzhz.com/linux39/mysql:5.7,harbor.zzhz.com/linux39/xtrabackup:1.0
#测试短和长域名
FQDN：$(podname).(headless server name)
FQDN：$(podname).(headless server name).namespace.svc.zzhz.local
[root@localhost7C mysql]# kubectl exec -it mysql-0 bash
root@mysql-0:/# hostname
mysql-0
root@mysql-0:/# ping mysql-1.mysql.default.svc.zzhz.local
root@mysql-0:/# ping mysql-0.mysql.default.svc.zzhz.local
root@mysql-0:/# ping mysql-1.mysql
标签：zzhz,StatefulSet,name,data,MySQL,PVC,xtrabackup,mysql,root From： https://www.cnblogs.com/Yuanbangchen/p/17309336.html