Kubernetes 构建高可用、高性能 Redis 集群实战指南
1. 部署方案规划
1.1 部署架构图
1.2 前提说明
- 本实战环境使用 NFS 作为 k8s 集群的持久化存储
- Redis 集群所有资源部署在命名空间 chengke 内。
2. 创建 ConfigMap
2.1 创建 ConfigMap
2.1.1 创建 Redis 配置文件
[root@k8s-m1 1]# cat redis-cluster-cm.yaml
apiVersion: v1
kind: ConfigMap
metadata:name: redis-cluster-config
data:redis-config: |appendonly yesprotected-mode nodir /dataport 6379cluster-enabled yescluster-config-file /data/nodes.confcluster-node-timeout 5000masterauth Chengke2025requirepass Chengke2025
2.1.2 创建资源
[root@k8s-m1 1]# kubectl apply -f redis-cluster-cm.yaml
2.1.3 验证资源
[root@k8s-m1 1]# kubectl get cm
NAME DATA AGE
redis-cluster-config 1 68m
2.2 创建 Redis
本文使用 StatefulSet 部署 Redis 服务,需要创建 StatefulSet 和 HeadLess 两种资源。
2.2.1 创建资源清单
[root@k8s-m1 1]# cat redis-cluster-sts.yaml
apiVersion: v1
kind: Service
metadata:name: redis-headlesslabels:app.kubernetes.io/name: redis-cluster
spec:ports:- name: redis-6379protocol: TCPport: 6379targetPort: 6379selector:app.kubernetes.io/name: redis-clusterclusterIP: Nonetype: ClusterIP
---
apiVersion: apps/v1
kind: StatefulSet
metadata:name: redis-clusterlabels:app.kubernetes.io/name: redis-cluster
spec:serviceName: redis-headlessreplicas: 6selector:matchLabels:app.kubernetes.io/name: redis-clustertemplate:metadata:labels:app.kubernetes.io/name: redis-clusterspec:affinity:podAntiAffinity:preferredDuringSchedulingIgnoredDuringExecution:- weight: 100podAffinityTerm:labelSelector:matchExpressions:- key: app.kubernetes.io/nameoperator: Invalues:- redis-clustertopologyKey: kubernetes.io/hostnamecontainers:- name: redisimage: redis:8.0.2imagePullPolicy: IfNotPresentcommand:- "redis-server"args:- "/etc/redis/redis.conf"- "--protected-mode"- "no"- "--cluster-announce-ip"- "$(POD_IP)"env:- name: POD_IPvalueFrom:fieldRef:fieldPath: status.podIPports:- name: redis-6379containerPort: 6379protocol: TCPvolumeMounts:- name: configmountPath: /etc/redis- name: redis-cluster-datamountPath: /dataresources:requests:cpu: 50mmemory: 500Milimits:cpu: "2"memory: 4Givolumes:- name: configconfigMap:name: redis-cluster-configitems:- key: redis-configpath: redis.confvolumeClaimTemplates:- metadata:name: redis-cluster-dataspec:accessModes:- ReadWriteOncestorageClassName: nfs-clientresources:requests:storage: 5Gi
注意: POD_IP 是重点,如果不配置会导致线上的 POD 重启换 IP 后,集群状态无法自动同步
2.2.2 创建资源
[root@k8s-master01 1]# kubectl apply -f redis-cluster-sts.yaml
service/redis-headless created
statefulset.apps/redis-cluster created
2.2.3 验证资源
执行下面的命令,查看 StatefulSet、Pod、Service 创建结果
[root@k8s-m1 1]# kubectl get pod,svc,sts
NAME READY STATUS RESTARTS AGE
pod/redis-cluster-0 1/1 Running 0 69m
pod/redis-cluster-1 1/1 Running 0 67m
pod/redis-cluster-2 1/1 Running 0 48m
pod/redis-cluster-3 1/1 Running 0 65m
pod/redis-cluster-4 1/1 Running 0 65m
pod/redis-cluster-5 1/1 Running 0 65m
pod/redisinsight-5cb887744f-79h5k 1/1 Running 0 42mNAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 8d
service/redis-cluster-external NodePort 10.5.96.53 <none> 6379:31379/TCP 62m
service/redis-headless ClusterIP None <none> 6379/TCP 69m
service/redisinsight-external NodePort 10.9.143.0 <none> 5540:31380/TCP 42mNAME READY AGE
statefulset.apps/redis-cluster 6/6 69m
2.3 创建 k8s 集群外部访问服务
2.3.1 编写资源
我们采用 NodePort 方式在 Kubernetes 集群外发布 Redis 服务,指定的端口为 31379。
[root@k8s-m1 1]# cat redis-cluster-svc-external.yaml
kind: Service
apiVersion: v1
metadata:name: redis-cluster-externallabels:app: redis-cluster-external
spec:ports:- protocol: TCPport: 6379targetPort: 6379nodePort: 31379selector:app.kubernetes.io/name: redis-clustertype: NodePort
2.3.2 创建资源
[root@k8s-master01 1]# kubectl apply -f redis-cluster-svc-external.yaml
service/redis-cluster-external created
2.3.3 验证资源
执行下面的命令,查看 Service 创建结果
[root@k8s-m1 1]# kubectl get endpointslice
NAME ADDRESSTYPE PORTS ENDPOINTS AGE
kubernetes IPv4 6443 192.168.10.11 24d
my-service-noselector-1 IPv4 80 192.168.10.12,192.168.10.13 18d
redis-cluster-external-qvl7h IPv4 6379 10.244.215.78,10.244.215.111,10.244.111.244 + 3 more... 65m
redis-headless-j2x96 IPv4 6379 10.244.111.251,10.244.215.111,10.244.215.73 + 3 more... 73m
redisinsight-external-b2vks IPv4 5540 10.244.111.252 45m
[root@k8s-m1 1]# kubectl get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 8d
redis-cluster-external NodePort 10.5.96.53 <none> 6379:31379/TCP 65m
redis-headless ClusterIP None <none> 6379/TCP 73m
redisinsight-external NodePort 10.9.143.0 <none> 5540:31380/TCP 46m
3. 创建 Redis 集群
Redis POD 创建完成后,不会自动创建 Redis 集群,需要手工执行集群初始化的命令,有自动创建和手工创建两种方式,二选一,建议选择自动。
3.1 自动创建 Redis 集群
执行下面的命令,自动创建 3 个 master 和 3 个 slave 的集群,中间需要输入一次 yes。
[root@k8s-m1 1]# kubectl exec -it redis-cluster-0 -- redis-cli -a Chengke2025 --cluster create --cluster-replicas 1 $(kubectl get pods -l app.kubernetes.io/name=redis-cluster -o jsonpath='{range.items[*]} {.status.podIP}:6379 {end}')
Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
>>> Performing hash slots allocation on 6 nodes...
Master[0] -> Slots 0 - 5460
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica 10.244.111.244:6379 to 10.244.111.251:6379
Adding replica 10.244.215.78:6379 to 10.244.215.111:6379
Adding replica 10.244.215.73:6379 to 10.244.111.253:6379
M: 80be000a17cc1b2d1d7180e722876d501c90c9a3 10.244.111.251:6379slots:[0-5460] (5461 slots) master
M: 01a21392ef5998e7da5d382a1ed6d0ec35bef845 10.244.215.111:6379slots:[5461-10922] (5462 slots) master
M: 8e009ec3ccc37b0810db6b1ffc5bd6c241c0cd31 10.244.111.253:6379slots:[10923-16383] (5461 slots) master
S: 48978e7c86fe9bf341880eb9cf1fac3aa8e48dc4 10.244.215.73:6379replicates 8e009ec3ccc37b0810db6b1ffc5bd6c241c0cd31
S: 0d8bab081a2125b7a83c67c588c2a9f93482d69a 10.244.111.244:6379replicates 80be000a17cc1b2d1d7180e722876d501c90c9a3
S: d7f1dc037259b2d2c155ac5a5c5c5b4b8f7818c4 10.244.215.78:6379replicates 01a21392ef5998e7da5d382a1ed6d0ec35bef845
Can I set the above configuration? (type 'yes' to accept): yes
>>> Nodes configuration updated
>>> Assign a different config epoch to each node
>>> Sending CLUSTER MEET messages to join the cluster
Waiting for the cluster to join
..
>>> Performing Cluster Check (using node 10.244.111.251:6379)
M: 80be000a17cc1b2d1d7180e722876d501c90c9a3 10.244.111.251:6379slots:[0-5460] (5461 slots) master1 additional replica(s)
S: 48978e7c86fe9bf341880eb9cf1fac3aa8e48dc4 10.244.215.73:6379slots: (0 slots) slavereplicates 8e009ec3ccc37b0810db6b1ffc5bd6c241c0cd31
S: 0d8bab081a2125b7a83c67c588c2a9f93482d69a 10.244.111.244:6379slots: (0 slots) slavereplicates 80be000a17cc1b2d1d7180e722876d501c90c9a3
M: 8e009ec3ccc37b0810db6b1ffc5bd6c241c0cd31 10.244.111.253:6379slots:[10923-16383] (5461 slots) master1 additional replica(s)
M: 01a21392ef5998e7da5d382a1ed6d0ec35bef845 10.244.215.111:6379slots:[5461-10922] (5462 slots) master1 additional replica(s)
S: d7f1dc037259b2d2c155ac5a5c5c5b4b8f7818c4 10.244.215.78:6379slots: (0 slots) slavereplicates 01a21392ef5998e7da5d382a1ed6d0ec35bef845
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
3.2 验证集群状态
[root@k8s-m1 1]# kubectl exec -it redis-cluster-0 -- redis-cli -p 6379 -a Chengke2025 cluster info
E0802 16:18:19.072387 92106 websocket.go:297] Unknown stream id 1, discarding messageWarning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
cluster_state:ok
cluster_slots_assigned:16384
cluster_slots_ok:16384
cluster_slots_pfail:0
cluster_slots_fail:0
cluster_known_nodes:6
cluster_size:3
cluster_current_epoch:6
cluster_my_epoch:1
cluster_stats_messages_ping_sent:6868
cluster_stats_messages_pong_sent:6767
cluster_stats_messages_sent:13635
cluster_stats_messages_ping_received:6762
cluster_stats_messages_pong_received:6867
cluster_stats_messages_meet_received:5
cluster_stats_messages_received:13634
total_cluster_links_buffer_limit_exceeded:0
4. 集群功能测试
4.1 压力测试
使用 Redis 自带的压力测试工具,测试 Redis 集群是否可用,并简单测试性能。
使用 set 和get命令,发送100000次请求,每个请求包含一个键值对,其中键是随机生成的,值的大小是100字节,同时有20个客户端并发执行。
测试 set 场景:
kubectl exec -it redis-cluster-0 -- redis-benchmark -h 192.168.10.11 -p 31379 -a Chengke2025 -t set -n 100000 -c 20 -d 100 --cluster
测试 get 场景:
[root@k8s-master01 1]# kubectl exec -it redis-cluster-0 -- redis-benchmark -h
192.168.10.11 -p 31379 -a Chengke2025 -t get -n 100000 -c 20 -d 100 --cluster
4.2 故障切换测试
4.2.1. 测试场景1:
测试:手动删除一个 Master 的 Slave,观察 Slave Pod 是否会自动重建并加入原有 Master。
结果: 原有 Slave IP 删除后自动重建,IP 变更为 一个新的IP,并自动加入原有的Master。
4.2.2. 测试场景2:
测试:手动删除 Master ,观察 Master Pod 是否会自动重建并重新变成 Master。
结果: 原有 Master IP 删除后自动重建, IP变更为一个新的IP,并重新变成Master
以上测试内容,仅是简单的故障切换测试,生产环境请增加更多的测试场景!!!