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Docker 学习 | 创建 Redis 集群

本文研究 Docker 如何创建 Redis 集群

准备工作

分片 + 高可用 + 负载均衡

TODO 图片

为Redis集群创建网卡

$ docker network create redis --subnet 172.38.0.0/16

docker network inspect redis
[
    {
        "Name": "redis",
        "Id": "5e57da31eae5c3492d092139450fa8976abc15719d2682dc17be0ffc73a4e7e9",
        "Created": "2021-09-30T00:44:29.939271085+08:00",
        "Scope": "local",
        "Driver": "bridge",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": {},
            "Config": [
                {
                    "Subnet": "172.18.0.0/16",
                    "Gateway": "172.18.0.1"
                }
            ]
        },
        "Internal": false,
        "Attachable": false,
        "Ingress": false,
        "ConfigFrom": {
            "Network": ""
        },
        "ConfigOnly": false,
        "Containers": {},
        "Options": {},
        "Labels": {}
    }
]

通过 Shell 脚本创建六个 Redis 配置

for port in $(seq 1 6);\
do \
mkdir -p /root/docker-test/redis/mydata/redis/node-${port}/conf
touch /root/docker-test/redis/mydata/redis/node-${port}/conf/redis.conf
cat  << EOF > /root/docker-test/redis/mydata/redis/node-${port}/conf/redis.conf
port 6379
bind 0.0.0.0
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
cluster-announce-ip 172.38.0.1${port}
cluster-announce-port 6379
cluster-announce-bus-port 16379
appendonly yes
EOF
done 

vim /root/docker-test/redis/mydata/redis/node-1/conf/redis.conf

启动Redis服务

docker run -p 6371:6379 -p 16371:16379 --name redis-1 \
-v /root/docker-test/redis/mydata/redis/node-1/data:/data \
-v /root/docker-test/redis/mydata/redis/node-1/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.11 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf


docker run -p 6372:6379 -p 16372:16379 --name redis-2 \
-v /root/docker-test/redis/mydata/redis/node-2/data:/data \
-v /root/docker-test/redis/mydata/redis/node-2/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.12 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf

docker run -p 6373:6379 -p 16373:16379 --name redis-3 \
-v /root/docker-test/redis/mydata/redis/node-3/data:/data \
-v /root/docker-test/redis/mydata/redis/node-3/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.13 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf

docker run -p 6374:6379 -p 16374:16379 --name redis-4 \
-v /root/docker-test/redis/mydata/redis/node-4/data:/data \
-v /root/docker-test/redis/mydata/redis/node-4/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.14 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf

docker run -p 6375:6379 -p 16375:16379 --name redis-5 \
-v /root/docker-test/redis/mydata/redis/node-5/data:/data \
-v /root/docker-test/redis/mydata/redis/node-5/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.15 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf

docker run -p 6376:6379 -p 16376:16379 --name redis-6 \
-v /root/docker-test/redis/mydata/redis/node-6/data:/data \
-v /root/docker-test/redis/mydata/redis/node-6/conf/redis.conf:/etc/redis/redis.conf \
-d --net redis --ip 172.38.0.16 redis:5.0.9-alpine3.11 redis-server /etc/redis/redis.conf

查看服务

docker ps
CONTAINER ID   IMAGE                    COMMAND                  CREATED              STATUS              PORTS                                                                                      NAMES
7118fd848c2e   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   37 seconds ago       Up 35 seconds       0.0.0.0:6376->6379/tcp, :::6376->6379/tcp, 0.0.0.0:16376->16379/tcp, :::16376->16379/tcp   redis-6
2ffcadf0502c   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   40 seconds ago       Up 39 seconds       0.0.0.0:6375->6379/tcp, :::6375->6379/tcp, 0.0.0.0:16375->16379/tcp, :::16375->16379/tcp   redis-5
766b6d549e34   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   44 seconds ago       Up 43 seconds       0.0.0.0:6374->6379/tcp, :::6374->6379/tcp, 0.0.0.0:16374->16379/tcp, :::16374->16379/tcp   redis-4
1df5978f6506   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   About a minute ago   Up About a minute   0.0.0.0:6373->6379/tcp, :::6373->6379/tcp, 0.0.0.0:16373->16379/tcp, :::16373->16379/tcp   redis-3
5c2a44097f1b   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   About a minute ago   Up About a minute   0.0.0.0:6372->6379/tcp, :::6372->6379/tcp, 0.0.0.0:16372->16379/tcp, :::16372->16379/tcp   redis-2
cb4b52984a05   redis:5.0.9-alpine3.11   "docker-entrypoint.s…"   About a minute ago   Up About a minute   0.0.0.0:6371->6379/tcp, :::6371->6379/tcp, 0.0.0.0:16371->16379/tcp, :::16371->16379/tcp   redis-1

创建集群

$ docker exec -it redis-1 /bin/sh

$ redis-cli --cluster create 172.38.0.11:6379 172.38.0.12:6379 172.38.0.13:6379 172.38.0.14:6379 172.38.0.15:6379 172.38.0.16:6379 --cluster-replicas 1

/data # ls
appendonly.aof  nodes.conf

>>> Performing hash slots allocation on 6 nodes...
Master[0] -> Slots 0 - 5460
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica 172.38.0.15:6379 to 172.38.0.11:6379
Adding replica 172.38.0.16:6379 to 172.38.0.12:6379
Adding replica 172.38.0.14:6379 to 172.38.0.13:6379
M: c7ea33c6860fefd31eeb24d86f23868dee7d1235 172.38.0.11:6379
   slots:[0-5460] (5461 slots) master
M: 1687d37587aa73fa878bf0f02ba1c07c87021a74 172.38.0.12:6379
   slots:[5461-10922] (5462 slots) master
M: d5bf0a7cc1d57d77db7ba84318b5ef981363161d 172.38.0.13:6379
   slots:[10923-16383] (5461 slots) master
S: 743d7976dd1bbee2d93332a9d5a8510b1a8a0f9d 172.38.0.14:6379
   replicates d5bf0a7cc1d57d77db7ba84318b5ef981363161d
S: eec9dcd743073a821375ed93931b54cd8646f31e 172.38.0.15:6379
   replicates c7ea33c6860fefd31eeb24d86f23868dee7d1235
S: 78bd3fed02a3640b917003c8ad76254a270ec4c4 172.38.0.16:6379
   replicates 1687d37587aa73fa878bf0f02ba1c07c87021a74
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 172.38.0.11:6379)
M: c7ea33c6860fefd31eeb24d86f23868dee7d1235 172.38.0.11:6379
   slots:[0-5460] (5461 slots) master
   1 additional replica(s)
S: 743d7976dd1bbee2d93332a9d5a8510b1a8a0f9d 172.38.0.14:6379
   slots: (0 slots) slave
   replicates d5bf0a7cc1d57d77db7ba84318b5ef981363161d
S: eec9dcd743073a821375ed93931b54cd8646f31e 172.38.0.15:6379
   slots: (0 slots) slave
   replicates c7ea33c6860fefd31eeb24d86f23868dee7d1235
M: d5bf0a7cc1d57d77db7ba84318b5ef981363161d 172.38.0.13:6379
   slots:[10923-16383] (5461 slots) master
   1 additional replica(s)
S: 78bd3fed02a3640b917003c8ad76254a270ec4c4 172.38.0.16:6379
   slots: (0 slots) slave
   replicates 1687d37587aa73fa878bf0f02ba1c07c87021a74
M: 1687d37587aa73fa878bf0f02ba1c07c87021a74 172.38.0.12:6379
   slots:[5461-10922] (5462 slots) master
   1 additional replica(s)
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.


# 集群创建成功

查看集群信息

$ redis-cli -c
$ cluster info
127.0.0.1:6379> cluster info
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:257
cluster_stats_messages_pong_sent:247
cluster_stats_messages_sent:504
cluster_stats_messages_ping_received:242
cluster_stats_messages_pong_received:257
cluster_stats_messages_meet_received:5
cluster_stats_messages_received:504
127.0.0.1:6379> $ cluster nodes

# 主从都正常运行
743d7976dd1bbee2d93332a9d5a8510b1a8a0f9d 172.38.0.14:6379@16379 slave d5bf0a7cc1d57d77db7ba84318b5ef981363161d 0 1632937462545 4 connected
eec9dcd743073a821375ed93931b54cd8646f31e 172.38.0.15:6379@16379 slave c7ea33c6860fefd31eeb24d86f23868dee7d1235 0 1632937463000 5 connected
d5bf0a7cc1d57d77db7ba84318b5ef981363161d 172.38.0.13:6379@16379 master - 0 1632937463000 3 connected 10923-16383
78bd3fed02a3640b917003c8ad76254a270ec4c4 172.38.0.16:6379@16379 slave 1687d37587aa73fa878bf0f02ba1c07c87021a74 0 1632937462946 6 connected
c7ea33c6860fefd31eeb24d86f23868dee7d1235 172.38.0.11:6379@16379 myself,master - 0 1632937462000 1 connected 0-5460
1687d37587aa73fa878bf0f02ba1c07c87021a74 172.38.0.12:6379@16379 master - 0 1632937463947 2 connected 5461-10922