Mysql Kubernetes:从部署移动到statefulset-从机密设置环境
Kubernetes文档指出,对于mysql pod,我们需要使用状态集,以避免在一个pod死亡时出现“大脑分裂”的情况,换句话说,声明一个数据将写入的“主”节点,如果该pod死亡,则选择新的主节点,这就是我希望此部署和服务转移到状态集的原因:Mysql Kubernetes:从部署移动到statefulset-从机密设置环境,mysql,kubernetes,kubernetes-pod,Mysql,Kubernetes,Kubernetes Pod,Kubernetes文档指出,对于mysql pod,我们需要使用状态集,以避免在一个pod死亡时出现“大脑分裂”的情况,换句话说,声明一个数据将写入的“主”节点,如果该pod死亡,则选择新的主节点,这就是我希望此部署和服务转移到状态集的原因: --- apiVersion: apps/v1 kind: Deployment metadata: name: mysql-container spec: replicas: 3
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: mysql-container
spec:
replicas: 3
selector:
matchLabels:
app: mysql-container
template:
metadata:
labels:
app: mysql-container
spec:
containers:
- name: mysql-container
image: mysql:dev
imagePullPolicy: "IfNotPresent"
envFrom:
- secretRef:
name: prod-secrets
ports:
- containerPort: 3306
# container (pod) path
volumeMounts:
- name: mysql-persistent-storage
mountPath: /data/db
# minikube path
volumes:
- name: mysql-persistent-storage
persistentVolumeClaim:
claimName: mysql-pvc
#resources:
# requests:
# memory: 300Mi
# cpu: 400m
# limits:
# memory: 400Mi
# cpu: 500m
restartPolicy: Always
---
apiVersion: v1
kind: Service
metadata:
name: mysql
spec:
# Open port 3306 only to pods in cluster
selector:
app: mysql-container
ports:
- name: mysql
port: 3306
protocol: TCP
targetPort: 3306
type: ClusterIP
我创建了以下有状态集:
在容器第一节中,指定了文件中的环境变量,即已删除
env:
- name: MYSQL_ALLOW_EMPTY_PASSWORD
value: "1"
状态集:
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 [[ $ordinal -eq 0 ]]; then
cp /mnt/config-map/master.cnf /mnt/conf.d/
else
cp /mnt/config-map/slave.cnf /mnt/conf.d/
fi
volumeMounts:
- name: conf
mountPath: /mnt/conf.d
- name: config-map
mountPath: /mnt/config-map
- name: clone-mysql
image: gcr.io/google-samples/xtrabackup:1.0
command:
- bash
- "-c"
- |
set -ex
# Skip the clone if data already exists.
[[ -d /var/lib/mysql/mysql ]] && exit 0
# Skip the clone on master (ordinal index 0).
[[ `hostname` =~ -([0-9]+)$ ]] || exit 1
ordinal=${BASH_REMATCH[1]}
[[ $ordinal -eq 0 ]] && exit 0
# Clone data from previous peer.
ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql
# Prepare the backup.
xtrabackup --prepare --target-dir=/var/lib/mysql
volumeMounts:
- name: data
mountPath: /var/lib/mysql
subPath: mysql
- name: conf
mountPath: /etc/mysql/conf.d
containers:
- name: mysql
image: mysql:dev
imagePullPolicy: "IfNotPresent"
envFrom:
- secretRef:
name: prod-secrets
ports:
- name: mysql
containerPort: 3306
volumeMounts:
- name: data
mountPath: /var/lib/mysql
subPath: mysql
- name: conf
mountPath: /etc/mysql/conf.d
resources:
#requests:
# cpu: 300m
# memory: 1Gi
livenessProbe:
exec:
command: ["mysqladmin", "ping"]
initialDelaySeconds: 30
periodSeconds: 10
timeoutSeconds: 5
readinessProbe:
exec:
# Check we can execute queries over TCP (skip-networking is off).
command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"]
initialDelaySeconds: 5
periodSeconds: 2
timeoutSeconds: 1
- name: xtrabackup
image: gcr.io/google-samples/xtrabackup:1.0
ports:
- name: xtrabackup
containerPort: 3307
command:
- bash
- "-c"
- |
set -ex
cd /var/lib/mysql
# Determine binlog position of cloned data, if any.
if [[ -f xtrabackup_slave_info && "x$(<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
- name: data
persistentVolumeClaim:
claimName: mysql-pvc
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: mysql-container
spec:
serviceName: mysql
replicas: 2
selector:
matchLabels:
app: mysql-container
template:
metadata:
labels:
app: mysql-container
spec:
containers:
- name: mysql-container
image: mysql:dev
imagePullPolicy: "IfNotPresent"
envFrom:
- secretRef:
name: prod-secrets
ports:
- containerPort: 3306
# container (pod) path
volumeMounts:
- name: mysql-persistent-storage
mountPath: /var/lib/mysql
resources:
requests:
memory: 300Mi
cpu: 400m
limits:
memory: 400Mi
cpu: 500m
restartPolicy: Always
volumeClaimTemplates:
- metadata:
name: mysql-persistent-storage
spec:
storageClassName: localstorage
accessModes: ["ReadWriteOnce"]
resources:
requests:
storage: 5Gi
selector:
matchLabels:
type: local
我有创建机密的环境文件:
kubectl create secret prod-secrets \
--from-env-file=env.example
问题是我无法访问mysql(拒绝访问),使用秘密指定的凭据访问POD,没有状态集,所有这些都可以正常工作。所有吊舱都在运行,日志中没有错误
如何将secrets中的值指定到Statefulset中
我假设我需要以某种方式将这些秘密传递给命令部分,但不知道如何,来自Kuberenets页面的示例假设不使用凭据
如果有不太复杂的方式使用mysql的状态集,请告诉我,谢谢。让我们开始创建一个秘密:
$kubectl create secret generic test secret--from literal=username='my-app'--from literal=password='39528$vdg7Jb'
$kubectl获取机密测试机密-o yaml
版本:v1
数据:
密码:Mzk1MjgkdmRnN0pi
用户名:bXktYXBw
种类:秘密
元数据:
名称:测试机密
名称空间:默认值
envFrom
:envFrom
将机密的所有数据定义为容器环境变量。机密中的键
成为Pod中的环境变量
名称
apiVersion:v1
种类:豆荚
元数据:
姓名:envfrom secret
名称空间:默认值
规格:
容器:
-名称:envars测试容器
图片:nginx
来自:
-秘书长:
名称:测试机密
检查环境:
$kubectl exec-it env来自机密打印env
.
.
密码=39528$vdg7Jb
用户名=我的应用程序
.
.
env
:key-value
对出现在env
列表中,或者希望使用key
名称以外的变量名设置env
时,可以从k8ssecret
设置env
,如下所示:
apiVersion:v1
种类:豆荚
元数据:
姓名:envfrom secret
名称空间:默认值
规格:
容器:
-名称:envars测试容器
图片:nginx
环境:
-姓名:用户名
价值来源:
secretKeyRef:
名称:测试机密
关键字:用户名
-名称:密码
价值来源:
secretKeyRef:
名称:测试机密
密钥:密码
检查env
:
$kubectl exec-it env来自机密打印env
.
.
用户名=我的应用程序
密码=39528$vdg7Jb
.
.
同样的过程也适用于部署、状态集、守护程序…最后,我通过创建卷模板,为每个pod创建PV,两个卷都是同步的,数据库中没有重复条目,如果一个节点出现故障,数据将被保留,从而避免了上述复杂情况 storage.yaml:
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: localstorage
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: Immediate
reclaimPolicy: Delete
allowVolumeExpansion: True
---
kind: PersistentVolume
apiVersion: v1
metadata:
name: mysql-01
labels:
type: local
spec:
storageClassName: localstorage
capacity:
storage: 5Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/mnt/mysql01"
---
kind: PersistentVolume
apiVersion: v1
metadata:
name: mysql-02
labels:
type: local
spec:
storageClassName: localstorage
capacity:
storage: 5Gi
accessModes:
- ReadWriteOnce
hostPath:
path: "/mnt/mysql02"
状态集:
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 [[ $ordinal -eq 0 ]]; then
cp /mnt/config-map/master.cnf /mnt/conf.d/
else
cp /mnt/config-map/slave.cnf /mnt/conf.d/
fi
volumeMounts:
- name: conf
mountPath: /mnt/conf.d
- name: config-map
mountPath: /mnt/config-map
- name: clone-mysql
image: gcr.io/google-samples/xtrabackup:1.0
command:
- bash
- "-c"
- |
set -ex
# Skip the clone if data already exists.
[[ -d /var/lib/mysql/mysql ]] && exit 0
# Skip the clone on master (ordinal index 0).
[[ `hostname` =~ -([0-9]+)$ ]] || exit 1
ordinal=${BASH_REMATCH[1]}
[[ $ordinal -eq 0 ]] && exit 0
# Clone data from previous peer.
ncat --recv-only mysql-$(($ordinal-1)).mysql 3307 | xbstream -x -C /var/lib/mysql
# Prepare the backup.
xtrabackup --prepare --target-dir=/var/lib/mysql
volumeMounts:
- name: data
mountPath: /var/lib/mysql
subPath: mysql
- name: conf
mountPath: /etc/mysql/conf.d
containers:
- name: mysql
image: mysql:dev
imagePullPolicy: "IfNotPresent"
envFrom:
- secretRef:
name: prod-secrets
ports:
- name: mysql
containerPort: 3306
volumeMounts:
- name: data
mountPath: /var/lib/mysql
subPath: mysql
- name: conf
mountPath: /etc/mysql/conf.d
resources:
#requests:
# cpu: 300m
# memory: 1Gi
livenessProbe:
exec:
command: ["mysqladmin", "ping"]
initialDelaySeconds: 30
periodSeconds: 10
timeoutSeconds: 5
readinessProbe:
exec:
# Check we can execute queries over TCP (skip-networking is off).
command: ["mysql", "-h", "127.0.0.1", "-e", "SELECT 1"]
initialDelaySeconds: 5
periodSeconds: 2
timeoutSeconds: 1
- name: xtrabackup
image: gcr.io/google-samples/xtrabackup:1.0
ports:
- name: xtrabackup
containerPort: 3307
command:
- bash
- "-c"
- |
set -ex
cd /var/lib/mysql
# Determine binlog position of cloned data, if any.
if [[ -f xtrabackup_slave_info && "x$(<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
- name: data
persistentVolumeClaim:
claimName: mysql-pvc
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: mysql-container
spec:
serviceName: mysql
replicas: 2
selector:
matchLabels:
app: mysql-container
template:
metadata:
labels:
app: mysql-container
spec:
containers:
- name: mysql-container
image: mysql:dev
imagePullPolicy: "IfNotPresent"
envFrom:
- secretRef:
name: prod-secrets
ports:
- containerPort: 3306
# container (pod) path
volumeMounts:
- name: mysql-persistent-storage
mountPath: /var/lib/mysql
resources:
requests:
memory: 300Mi
cpu: 400m
limits:
memory: 400Mi
cpu: 500m
restartPolicy: Always
volumeClaimTemplates:
- metadata:
name: mysql-persistent-storage
spec:
storageClassName: localstorage
accessModes: ["ReadWriteOnce"]
resources:
requests:
storage: 5Gi
selector:
matchLabels:
type: local
@xerks据我所知,您从yaml中删除了一个硬编码的
env
,并希望通过k8s机密传递它。现在您是说需要使用env
文件?你能告诉我们吗?我有一个env文件,我从中创建了secret,kubectl create secret prod secrets--from env file=env.example
这在没有statefulset的情况下可以正常工作,我可以使用该文件中指定的凭据登录mysql数据库,但在使用statefulset时不起作用,我怀疑我需要以某种方式将这个秘密传递给init脚本,但不知道如果您已经有一个mysql数据库,为什么要尝试使用statefulset安装另一个数据库?您是否试图使用另一个数据库(在statefulset之前工作正常的数据库)的凭据访问新数据库(使用statefulset创建的数据库)?我想使用statefulset使数据在一个节点出现故障时保持一致,Kubernetes文档说,对于数据库,我们需要使用statefulset,因此我遇到了他们的示例,如果有更好的方法使用mysql的状态集,请让我知道,谢谢。我是kubernetes新手如果您是kubernetes新手,我建议您使用将mysql数据库安装到集群中。您还应该查看和文档。