部署集群过程中遇到的坑：
1 node(s) had taints that the pod didn't tolerate.
集群中有个节点被污染了，查看节点信息，发现其中一个节点没有起来，导致只能启动2个pod
2 PV和PVC上的坑
一个zk.yaml中需要创建3个zookeeper，根据zookeeper集群的特性，三个zookeeper需要三个不同的数据目录（如果再添加日志目录也是一样），集群才会正常起来
创建PV的时候需要创建三个不同的PV
在一个zk.yaml中，PVC需要关联到后端不同的三个PVC，如果按照传统的创建PVC，并在zk.yaml中指定PVC的名字，只能指定一个名字，这样是办不到关联到三个不同的PV，于是需要volumeClaimTemplates（PVC模板），模板accessModes需要ReadWriteOnce,ReadWriteMany会关联失败。
volumeClaimTemplates:
- metadata:
name: datadir
spec:
accessModes: [ "ReadWriteOnce" ]
resources:
requests:
storage: 1Gi
3 zookeeper提供给外部访问
zookeeper由于是使用statefulSet部署，使用到了无头服务，如果提供给外部访问呢？办法就是增加一个专门为外部访问的service。
具体部署
1 在192.168.0.11上创建安装nfs，并配置启动nfs
2 在每个node节点上下载nfs
3 在matser节点创建zk使用的PV
apiVersion: v1
kind: PersistentVolume
metadata:
name: zk-data1
spec:
capacity:
storage: 1Gi
accessModes:
- ReadWriteOnce
nfs:
server: 192.168.0.11
path: /data/zk/data1
---
apiVersion: v1
kind: PersistentVolume
metadata:
name: zk-data2
spec:
capacity:
storage: 1Gi
accessModes:
- ReadWriteOnce
nfs:
server: 192.168.0.11
path: /data/zk/data2
---
apiVersion: v1
kind: PersistentVolume
metadata:
name: zk-data3
spec:
capacity:
storage: 1Gi
accessModes:
- ReadWriteOnce
nfs:
server: 192.168.0.11
path: /data/zk/data3
4 在master节点上创建zookeeper的创建pod的yaml文件
参考官方文档：https://kubernetes.io/docs/tutorials/stateful-application/zookeeper/https://kubernetes.io/docs/tutorials/stateful-application/zookeeper/
官方文档中的镜像地址为国外地址，我这里网上找了一个可用的地址，跟官方镜像一样
[root@localhost zk]# cat zk.yaml
apiVersion: v1
kind: Service
metadata:
name: zk-hs
labels:
app: zk
spec:
ports:
- port: 2888
name: server
- port: 3888
name: leader-election
clusterIP: None
selector:
app: zk
---
apiVersion: v1
kind: Service
metadata:
name: zk-cs
labels:
app: zk
spec:
type: NodePort
ports:
- port: 2181
targetPort: 2181
name: client
nodePort: 2181
selector:
app: zk
---
apiVersion: policy/v1beta1
kind: PodDisruptionBudget
metadata:
name: zk-pdb
spec:
selector:
matchLabels:
app: zk
maxUnavailable: 1
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: zok
spec:
serviceName: zk-hs
replicas: 3
selector:
matchLabels:
app: zk
template:
metadata:
labels:
app: zk
spec:
affinity:
podAntiAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
- labelSelector:
matchExpressions:
- key: "app"
operator: In
values:
- zk
topologyKey: "kubernetes.io/hostname"
containers:
- name: kubernetes-zookeeper
imagePullPolicy: Always
image: leolee32/kubernetes-library:kubernetes-zookeeper1.0-3.4.10
resources:
requests:
memory: "1Gi"
cpu: "0.5"
ports:
- containerPort: 2181
name: client
- containerPort: 2888
name: server
- containerPort: 3888
name: leader-election
command:
- sh
- -c
- "start-zookeeper \
--servers=3 \
--data_dir=/var/lib/zookeeper/data \
--data_log_dir=/var/lib/zookeeper/data/log \
--conf_dir=/opt/zookeeper/conf \
--client_port=2181 \
--election_port=3888 \
--server_port=2888 \
--tick_time=2000 \
--init_limit=10 \
--sync_limit=5 \
--heap=512M \
--max_client_cnxns=60 \
--snap_retain_count=3 \
--purge_interval=12 \
--max_session_timeout=40000 \
--min_session_timeout=4000 \
--log_level=INFO"
readinessProbe:
exec:
command:
- sh
- -c
- "zookeeper-ready 2181"
initialDelaySeconds: 10
timeoutSeconds: 5
livenessProbe:
exec:
command:
- sh
- -c
- "zookeeper-ready 2181"
initialDelaySeconds: 10
timeoutSeconds: 5
volumeMounts:
- name: datadir
mountPath: /var/lib/zookeeper
volumeClaimTemplates:
- metadata:
name: datadir
spec:
accessModes: [ "ReadWriteOnce" ]
resources:
requests:
storage: 1Gi
5 查看集群状态
for i in 0 1 2; do kubectl exec zok-$i zkServer.sh status; done
6 外部访问zookeeper集群（使用本机电脑访问）
