一 關(guān)系型數(shù)據(jù)庫和 NoSQL 數(shù)據(jù)庫

數(shù)據(jù)庫主要分為兩大類：關(guān)系型數(shù)據(jù)庫與 NoSQL 數(shù)據(jù)庫

二 Remote Dictionary Server 簡介

中文官網(wǎng)?? https://redis.cn

什么是redis ?

Redis (Remote Dictionary Server)

在 2009 年發(fā)布，開發(fā)者是意大利的薩爾瓦多 · 桑菲利波普（ Salvatore Sanfilippo ），他本想為自己的公司開發(fā)一個用于替換MySQL 的產(chǎn)品 Redis ，但是沒有想到他把 Redis 開源后大受歡迎，短短幾年， Redis 就有了很大的用戶群體，目前國內(nèi)外使用的公司眾多, 比如 : 阿里 , 百度 , 新浪微博 , 知乎網(wǎng) ,GitHub,Twitter 等

Redis 是一個開源的、遵循 BSD 協(xié)議的、基于內(nèi)存的而且目前比較流行的鍵值數(shù)據(jù)庫 (key-value database)，是一個非關(guān)系型數(shù)據(jù)庫， redis 提供將內(nèi)存通過網(wǎng)絡(luò)遠(yuǎn)程共享的一種服務(wù)，提供類似功能的還有memcached ，但相比 memcached ， redis 還提供了易擴(kuò)展、高性能、具備數(shù)據(jù)持久性等功能。

Redis 在高并發(fā)、低延遲環(huán)境要求比較高的環(huán)境使用量非常廣泛。

Redis特性 ?

• 速度快: 10W QPS,基于內(nèi)存,C語言實(shí)現(xiàn)
• 單線程
• 持久化
• 支持多種數(shù)據(jù)結(jié)構(gòu)
• 支持多種編程語言
• 功能豐富: 支持Lua腳本,發(fā)布訂閱,事務(wù),pipeline等功能
• 簡單: 代碼短小精悍(單機(jī)核心代碼只有23000行左右),單線程開發(fā)容易,不依賴外部庫,使用簡單
• 主從復(fù)制
• 支持高可用和分布式

• 純內(nèi)存
• 非阻塞
• 避免線程切換和競態(tài)消耗

?Redis應(yīng)用場景

• Session 共享：常見于web集群中的Tomcat或者PHP中多web服務(wù)器session共享
• 緩存：數(shù)據(jù)查詢、電商網(wǎng)站商品信息、新聞內(nèi)容
• 計數(shù)器：訪問排行榜、商品瀏覽數(shù)等和次數(shù)相關(guān)的數(shù)值統(tǒng)計場景
• 微博/微信社交場合：共同好友,粉絲數(shù),關(guān)注,點(diǎn)贊評論等
• 消息隊列：ELK的日志緩存、部分業(yè)務(wù)的訂閱發(fā)布系統(tǒng)
• 地理位置: 基于GEO(地理信息定位),實(shí)現(xiàn)搖一搖,附近的人,外賣等功能

?緩存的實(shí)現(xiàn)流程

數(shù)據(jù)更新操作流程

數(shù)據(jù)讀操作流程

?三 Redis的安裝

官方下載地址：http://download.redis.io/releases/ ?

?源碼安裝

[root@redis-node1 ~]# tar zxf redis-7.4.0.tar.gz #壓縮包自行下載
[root@redis-node1 ~]# ls
anaconda-ks.cfg  redis-7.4.0  redis-7.4.0.tar.gz
[root@redis-node1 ~]# yum install make gcc initscripts -y #安裝編譯工具#執(zhí)行編譯命令
[root@redis-node1 redis-7.4.0]# make && make install[root@redis-node1 redis-7.4.0]# cd utils/
[root@redis-node1 utils]# vim install_server.sh #講一下內(nèi)容注釋掉#bail if this system is managed by systemd#_pid_1_exe="$(readlink -f /proc/1/exe)"#if [ "${_pid_1_exe##*/}" = systemd ]#then# echo "This systems seems to use systemd."# echo "Please take a look at the provided example service unit files in this     directory, and adapt and install them. Sorry!"# exit 1#fi[root@redis-node1 utils]# ./install_server.sh
Welcome to the redis service installer
This script will help you easily set up a running redis serverPlease select the redis port for this instance: [6379]
Selecting default: 6379
Please select the redis config file name [/etc/redis/6379.conf]
Selected default - /etc/redis/6379.conf
Please select the redis log file name [/var/log/redis_6379.log]
Selected default - /var/log/redis_6379.log
Please select the data directory for this instance [/var/lib/redis/6379]
Selected default - /var/lib/redis/6379
Please select the redis executable path [/usr/local/bin/redis-server]
Selected config:
Port           : 6379
Config file    : /etc/redis/6379.conf
Log file       : /var/log/redis_6379.log
Data dir       : /var/lib/redis/6379
Executable     : /usr/local/bin/redis-server
Cli Executable : /usr/local/bin/redis-cli
Is this ok? Then press ENTER to go on or Ctrl-C to abort.
Copied /tmp/6379.conf => /etc/init.d/redis_6379
Installing service...
Successfully added to chkconfig!
Successfully added to runlevels 345!
Starting Redis server...
Installation successful![root@redis-node1 utils]# vim /etc/redis/6379.conf #修改以下參數(shù)
bind * -::*
protected-mode no[root@redis-node1 utils]# /etc/init.d/redis_6379 restart
Stopping ...
Redis stopped
Starting Redis server...[root@redis-node1 utils]# netstat -antlupe | grep redis
tcp        0      0 0.0.0.0:6379            0.0.0.0:*               LISTEN      0          31759      7611/redis-server *
tcp6       0      0 :::6379                 :::*                    LISTEN      0          31760      7611/redis-server *[root@redis-node1 utils]# redis-cli
127.0.0.1:6379>

四 Redis 主從復(fù)制

配置主從同步?

1.修改mastser節(jié)點(diǎn)的配置文件

[root@redis-node1 bin]# vim /etc/redis/6379.confprotected-mode no #關(guān)閉protected模式[root@redis-node1 utils]# /etc/init.d/redis_6379 restart

2.配置slave節(jié)點(diǎn)

[root@redis-node2 bin]# vim /etc/redis/6379.confprotected-mode no #關(guān)閉protected模式
replicaof 172.25.254.10 6379[root@redis-node2 utils]# /etc/init.d/redis_6379 restart[root@redis-node3 bin]# vim /etc/redis/6379.confprotected-mode no #關(guān)閉protected模式
replicaof 172.25.254.100 6379[root@redis-node3 utils]# /etc/init.d/redis_6379 restart

3.測試效果 ?

[root@redis-node1 bin]# redis-cli
127.0.0.1:6379> INFO replication
# Replication
role:master
connected_slaves:2
slave0:ip=172.25.254.20,port=6379,state=online,offset=2636,lag=1
slave1:ip=172.25.254.30,port=6379,state=online,offset=2636,lag=0
master_failover_state:no-failover
master_replid:2aac666a85461a4af445c6f48397a074ea2a500e
master_replid2:0000000000000000000000000000000000000000
master_repl_offset:2636
second_repl_offset:-1
repl_backlog_active:1
repl_backlog_size:1048576
repl_backlog_first_byte_offset:1
repl_backlog_histlen:2636127.0.0.1:6379> set name zhangsan
OK[root@redis-node2 utils]# redis-cli
127.0.0.1:6379> get name
"zhangsan"[root@redis-node3 utils]# redis-cli
127.0.0.1:6379> get name
"zhangsan"

主從同步過程

• slave節(jié)點(diǎn)發(fā)送同步親求到master節(jié)點(diǎn)
• slave節(jié)點(diǎn)通過master節(jié)點(diǎn)的認(rèn)證開始進(jìn)行同步
• master節(jié)點(diǎn)會開啟bgsave進(jìn)程發(fā)送內(nèi)存rbd到slave節(jié)點(diǎn)，在此過程中是異步操作，也就是說 master節(jié)點(diǎn)仍然可以進(jìn)行寫入動作
• slave節(jié)點(diǎn)收到rdb后首先清空自己的所有數(shù)據(jù)
• slave節(jié)點(diǎn)加載rdb并進(jìn)行數(shù)據(jù)恢復(fù)
• 在master和slave同步過程中master還會開啟新的bgsave進(jìn)程把沒有同步的數(shù)據(jù)進(jìn)行緩存
• 然后通過自有的replactionfeedslave函數(shù)把未通過內(nèi)存快照發(fā)動到slave的數(shù)據(jù)一條一條寫入到

?Redis哨兵

1.在master節(jié)點(diǎn)中

#編輯配置文件
[root@redis-node1 ~]# cd redis-7.4.0/
[root@redis-node1 redis-7.4.0]# cp sentinel.conf /etc/redis/
[root@redis-node1 redis-7.4.0]# vim /etc/redis/sentinel.conf
protected-mode no #關(guān)閉保護(hù)模式
port 26379 #監(jiān)聽端口
daemonize no #進(jìn)入不打如后臺
pidfile /var/run/redis-sentinel.pid #sentinel進(jìn)程pid文件
loglevel notice #日志級別
sentinel monitor mymaster 172.25.254.100 6379 2 #創(chuàng)建sentinel監(jiān)控監(jiān)控master主
機(jī)，2表示必須得到2票
sentinel down-after-milliseconds mymaster 10000 #master中斷時長，10秒連不上視為
master下線
sentinel parallel-syncs mymaster 1 #發(fā)生故障轉(zhuǎn)移后，同時開始同步新
master數(shù)據(jù)的slave數(shù)量
sentinel failover-timeout mymaster 180000 #整個故障切換的超時時間為3分鐘
####復(fù)制配置文件到其他階段
[root@redis-node1 redis-7.4.0]# scp /etc/redis/sentinel.conf
root@172.25.254.20:/etc/redis/[root@redis-node1 redis-7.4.0]# scp /etc/redis/sentinel.conf
root@172.25.254.30:/etc/redis/

?2 啟動服務(wù)

[root@redis-node1 redis]# redis-sentinel /etc/redis/sentinel.conf
8186:X 08 Sep 2024 18:28:42.695 # WARNING Memory overcommit must be enabled! Without it, a background save or replication may fail under low memory condition. Being disabled, it can also cause failures without low memory condition, see https://github.com/jemalloc/jemalloc/issues/1328. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.
8186:X 08 Sep 2024 18:28:42.695 * oO0OoO0OoO0Oo Redis is starting oO0OoO0OoO0Oo
8186:X 08 Sep 2024 18:28:42.695 * Redis version=7.4.0, bits=64, commit=00000000, modified=0, pid=8186, just started
8186:X 08 Sep 2024 18:28:42.695 * Configuration loaded
8186:X 08 Sep 2024 18:28:42.696 * Increased maximum number of open files to 10032 (it was originally set to 1024).
8186:X 08 Sep 2024 18:28:42.696 * monotonic clock: POSIX clock_gettime_.__.-``__ ''-.__.-``    `.  `_.  ''-._           Redis Community Edition.-`` .-```.  ```\/    _.,_ ''-._     7.4.0 (00000000/0) 64 bit(    '      ,       .-`  | `,    )     Running in sentinel mode|`-._`-...-` __...-.``-._|'` _.-'|     Port: 26379|    `-._   `._    /     _.-'    |     PID: 8186`-._    `-._  `-./  _.-'    _.-'|`-._`-._    `-.__.-'    _.-'_.-'||    `-._`-._        _.-'_.-'    |           https://redis.io`-._    `-._`-.__.-'_.-'    _.-'|`-._`-._    `-.__.-'    _.-'_.-'||    `-._`-._        _.-'_.-'    |`-._    `-._`-.__.-'_.-'    _.-'`-._    `-.__.-'    _.-'`-._        _.-'`-.__.-'8186:X 08 Sep 2024 18:28:42.698 * Sentinel new configuration saved on disk
8186:X 08 Sep 2024 18:28:42.699 * Sentinel ID is 6f61c9c00908c018579564cacb1b87ce1819ae39
8186:X 08 Sep 2024 18:28:42.699 # +monitor master mymaster 172.25.254.10 6379 quorum 2
8186:X 08 Sep 2024 18:28:42.699 * +slave slave 172.25.254.20:6379 172.25.254.20 6379 @ mymaster 172.25.254.10 6379
8186:X 08 Sep 2024 18:28:42.701 * Sentinel new configuration saved on disk
8186:X 08 Sep 2024 18:28:42.701 * +slave slave 172.25.254.30:6379 172.25.254.30 6379 @ mymaster 172.25.254.10 6379
8186:X 08 Sep 2024 18:28:42.702 * Sentinel new configuration saved on disk
8186:X 08 Sep 2024 18:29:05.029 * +sentinel sentinel 4a69b2501e30133613ef79a691fb79e469987a2a 172.25.254.20 26379 @ mymaster 172.25.254.10 6379
8186:X 08 Sep 2024 18:29:05.031 * Sentinel new configuration saved on disk
8186:X 08 Sep 2024 18:29:15.502 * +sentinel sentinel b6de2cc3781faf822bf6a89b9c8d70e5b9a2d0c9 172.25.254.30 26379 @ mymaster 172.25.254.10 6379
8186:X 08 Sep 2024 18:29:15.504 * Sentinel new configuration saved on disk
8186:X 08 Sep 2024 18:30:03.421 # +sdown master mymaster 172.25.254.10 6379
8186:X 08 Sep 2024 18:30:03.457 * Sentinel new configuration saved on disk

注意：/etc/redis/sentinel.conf 文件在用哨兵程序調(diào)用后會更改其配置文件，如果需要重新做需要刪掉文件重新編輯

測試：

[root@redis-node1 ~]# redis-cli
127.0.0.1:6379> info replication
# Replication
role:master
connected_slaves:2
slave0:ip=172.25.254.20,port=6379,state=online,offset=31425,lag=0
slave1:ip=172.25.254.30,port=6379,state=online,offset=31425,lag=0
master_failover_state:no-failover
master_replid:f5747c81b81bc83acf68a269251225721fbf810e
master_replid2:f289a3b72a069a75915690ba0f102e8f08b7a074
master_repl_offset:31707
second_repl_offset:23776
repl_backlog_active:1
repl_backlog_size:1048576
repl_backlog_first_byte_offset:23776
repl_backlog_histlen:7932
127.0.0.1:6379> SHUTDOWN
(0.92s)[root@redis-node2 ~]# redis-cli
127.0.0.1:6379> info replication
# Replication
role:master
connected_slaves:1
slave0:ip=172.25.254.30,port=6379,state=online,offset=44414,lag=0
master_failover_state:no-failover
master_replid:988d209809c7e1980bb24f83f53964a750e0cf81
master_replid2:f5747c81b81bc83acf68a269251225721fbf810e
master_repl_offset:44555
second_repl_offset:34875
repl_backlog_active:1
repl_backlog_size:1048576
repl_backlog_first_byte_offset:15
repl_backlog_histlen:44541

在整個架構(gòu)中可能會出現(xiàn)的問題

問題：

在生產(chǎn)環(huán)境中如果 master 和 slave 中的網(wǎng)絡(luò)出現(xiàn)故障，由于哨兵的存在會把 master 提出去

當(dāng)網(wǎng)絡(luò)恢復(fù)后， master 發(fā)現(xiàn)環(huán)境發(fā)生改變， master 就會把自己的身份轉(zhuǎn)換成 slave

master 變成 slave 后會把網(wǎng)絡(luò)故障那段時間寫入自己中的數(shù)據(jù)清掉，這樣數(shù)據(jù)就丟失了。

解決：

master 在被寫入數(shù)據(jù)時會持續(xù)連接 slave ， mater 確保有 2 個 slave 可以寫入我才允許寫入

如果 slave 數(shù)量少于 2 個便拒絕寫入。

#在master中配置
[root@redis-node2 ~]# redis-cli
127.0.0.1:6379> config get min-slaves-to-write
1) "min-slaves-to-write"
2) "0"
127.0.0.1:6379> config set min-slaves-to-write 2
OK
127.0.0.1:6379> config get min-slaves-to-write
1) "min-slaves-to-write"
2) "2"
##################################以上為臨時修改#永久修改
[root@redis-node2 ~]# vim /etc/redis/6379.conf
min-slaves-to-write 2

?六?Redis Cluster（無中心化設(shè)計）

Redis Cluster 工作原理

Redis Cluster特點(diǎn)如下
1. 所有Redis節(jié)點(diǎn)使用(PING機(jī)制)互聯(lián)
2. 集群中某個節(jié)點(diǎn)的是否失效，是由整個集群中超過半數(shù)的節(jié)點(diǎn)監(jiān)測都失效，才能算真正的失效
3. 客戶端不需要proxy即可直接連接redis，應(yīng)用程序中需要配置有全部的redis服務(wù)器IP
4. redis cluster把所有的redis node 平均映射到 0-16383個槽位(slot)上，讀寫需要到指定的redis node上進(jìn)行操作，因此有多少個redis node相當(dāng)于redis 并發(fā)擴(kuò)展了多少倍，每個redis node承擔(dān)16384/N個槽位
5. Redis cluster預(yù)先分配16384個(slot)槽位，當(dāng)需要在redis集群中寫入一個key -value的時候，會使用CRC16(key) mod 16384之后的值，決定將key寫入值哪一個槽位從而決定寫入哪一個Redis節(jié)點(diǎn)上，從而有效解決單機(jī)瓶頸。

Redis cluster 架構(gòu)

假如三個主節(jié)點(diǎn)分別是： A, B, C 三個節(jié)點(diǎn)，采用哈希槽 (hash slot) 的方式來分配 16384 個 slot 的話它們

三個節(jié)點(diǎn)分別承擔(dān)的 slot 區(qū)間可以是：

節(jié)點(diǎn) A 覆蓋 0 － 5460

節(jié)點(diǎn) B 覆蓋 5461 － 10922

節(jié)點(diǎn) C 覆蓋 10923 － 16383

?

?Redis Cluster 部署架構(gòu)說明

創(chuàng)建redis cluster的前提?

?部署redis cluster

[root@redis-node1 ~]# vim /etc/redis/redis.conf #修改以下參數(shù)
bind * -::*
masterauth "123456" #集群主從認(rèn)證requirepass "123456" #redis登陸密碼 redis-cli 命令連接redis后要用“auth 密碼”進(jìn)行認(rèn)證cluster-enabled yes #開啟cluster集群功能cluster-config-file nodes-6379.conf #指定集群配置文件cluster-node-timeout 15000 #節(jié)點(diǎn)加入集群的超時時間單位是ms[root@redis-node1 ~]# systemctl restart redis.service[root@redis-node1 ~]# redis-cli
127.0.0.1:6379> info
NOAUTH Authentication required.
127.0.0.1:6379> AUTH 123456
OK
127.0.0.1:6379> info#其他主機(jī)均要配置以上配置（簡便方案）
[root@redis-node1 ~]# for i in 20 30 110 120 130 ;do scp /etc/redis/redis.conf root@172.25.254.$i:/etc/redis/redis.conf ; done
#再重啟服務(wù)

[root@redis-node1 ~]# redis-cli  --cluster help
Cluster Manager Commands:
create host1:port1 ... hostN:portN #創(chuàng)建集群
--cluster-replicas <arg> #指定master的副本數(shù)check <host:port> or <host> <port> #檢測集群信息info <host:port> or <host> <port> #查看集群信息fix <host:port> or <host> <port> #修復(fù)集群reshard <host:port> or <host> <port> #在線熱遷移集群指定主機(jī)的slots數(shù)據(jù)rebalance <host:port> or <host> <port> #平衡各集群主機(jī)的slot數(shù)量add-node new_host:new_port existing_host:existing_port #添加主機(jī)del-node host:port node_id #刪除主機(jī)import host:port #導(dǎo)入外部redis服務(wù)器的數(shù)據(jù)到
當(dāng)前集群

[root@redis-node1 ~]# redis-cli  --cluster  create -a 123456 \
> 172.25.254.10:6379 172.25.254.20:6379 172.25.254.30:6379 \
> 172.25.254.110:6379 172.25.254.120:6379 172.25.254.130:6379 \
> --cluster-replicas 1
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 #哈希槽分配
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica 172.25.254.120:6379 to 172.25.254.10:6379 #主從分配情況
Adding replica 172.25.254.130:6379 to 172.25.254.20:6379
Adding replica 172.25.254.110:6379 to 172.25.254.30:6379
M: c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea 172.25.254.10:6379slots:[0-5460] (5461 slots) master
M: 5614ce1e5d6c25524126130864b7eea815c373a0 172.25.254.20:6379slots:[5461-10922] (5462 slots) master
M: f2a85df5b5355b3fd7ded898552b8bbfd2c2f925 172.25.254.30:6379slots:[10923-16383] (5461 slots) master
S: adf52933b7434c129b81292b47103e6b1eab23fb 172.25.254.110:6379replicates f2a85df5b5355b3fd7ded898552b8bbfd2c2f925
S: b3f4291d1a2313d3a9907bf65e8287f488292c66 172.25.254.120:6379replicates c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea
S: aee197141809a2f031f7e952d504c6aa9dd0c0c3 172.25.254.130:6379replicates 5614ce1e5d6c25524126130864b7eea815c373a0
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 172.25.254.10:6379)
M: c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea 172.25.254.10:6379slots:[0-5460] (5461 slots) master1 additional replica(s)
S: aee197141809a2f031f7e952d504c6aa9dd0c0c3 172.25.254.130:6379slots: (0 slots) slavereplicates 5614ce1e5d6c25524126130864b7eea815c373a0
S: b3f4291d1a2313d3a9907bf65e8287f488292c66 172.25.254.120:6379slots: (0 slots) slavereplicates c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea
M: f2a85df5b5355b3fd7ded898552b8bbfd2c2f925 172.25.254.30:6379slots:[10923-16383] (5461 slots) master1 additional replica(s)
S: adf52933b7434c129b81292b47103e6b1eab23fb 172.25.254.110:6379slots: (0 slots) slavereplicates f2a85df5b5355b3fd7ded898552b8bbfd2c2f925
M: 5614ce1e5d6c25524126130864b7eea815c373a0 172.25.254.20:6379slots:[5461-10922] (5462 slots) master1 additional replica(s)
[OK] All nodes agree about slots configuration.
>>> Check for open slots...    #檢查打開的哈希槽位
>>> Check slots coverage...    #檢查槽位覆蓋范圍
[OK] All 16384 slots covered.    #所有槽位分配完成

?檢測redis集群狀態(tài)

[root@redis-node1 ~]# redis-cli -a 123456 --cluster info 172.25.254.10:6379
Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
172.25.254.10:6379 (c0b144b6...) -> 0 keys | 5461 slots | 1 slaves.
172.25.254.30:6379 (f2a85df5...) -> 0 keys | 5461 slots | 1 slaves.
172.25.254.20:6379 (5614ce1e...) -> 0 keys | 5462 slots | 1 slaves.
[OK] 0 keys in 3 masters.
0.00 keys per slot on average.
[root@redis-node1 ~]# redis-cli -a 123456 --cluster check 172.25.254.10:6379
Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
172.25.254.10:6379 (c0b144b6...) -> 0 keys | 5461 slots | 1 slaves.
172.25.254.30:6379 (f2a85df5...) -> 0 keys | 5461 slots | 1 slaves.
172.25.254.20:6379 (5614ce1e...) -> 0 keys | 5462 slots | 1 slaves.
[OK] 0 keys in 3 masters.
0.00 keys per slot on average.
>>> Performing Cluster Check (using node 172.25.254.10:6379)
M: c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea 172.25.254.10:6379slots:[0-5460] (5461 slots) master1 additional replica(s)
S: aee197141809a2f031f7e952d504c6aa9dd0c0c3 172.25.254.130:6379slots: (0 slots) slavereplicates 5614ce1e5d6c25524126130864b7eea815c373a0
S: b3f4291d1a2313d3a9907bf65e8287f488292c66 172.25.254.120:6379slots: (0 slots) slavereplicates c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea
M: f2a85df5b5355b3fd7ded898552b8bbfd2c2f925 172.25.254.30:6379slots:[10923-16383] (5461 slots) master1 additional replica(s)
S: adf52933b7434c129b81292b47103e6b1eab23fb 172.25.254.110:6379slots: (0 slots) slavereplicates f2a85df5b5355b3fd7ded898552b8bbfd2c2f925
M: 5614ce1e5d6c25524126130864b7eea815c373a0 172.25.254.20:6379slots:[5461-10922] (5462 slots) master1 additional replica(s)
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.

[root@redis-node1 ~]# redis-cli -a 123456
Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
127.0.0.1:6379> set name haha
(error) MOVED 5798 172.25.254.20:6379 #被分配到172.25.254.20的hash槽位上[root@redis-node2 ~]# redis-cli
127.0.0.1:6379> AUTH 123456
OK
127.0.0.1:6379>  set name haha
OK

#添加master
[root@redis-node2 ~]# redis-cli -a 123456 --cluster add-node 172.25.254.50:6379 172.25.254.20:6379#分配槽位
[root@redis-node2 ~]# redis-cli -a 123456 --cluster reshard 172.25.254.20:6379
Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
>>> Performing Cluster Check (using node 172.25.254.20:6379)
M: 5614ce1e5d6c25524126130864b7eea815c373a0 172.25.254.20:6379slots:[5461-10922] (5462 slots) master1 additional replica(s)
M: c2ee7a506d8cc97b8f1b3b697d30aae90d51890a 172.25.254.50:6379slots: (0 slots) master
M: f2a85df5b5355b3fd7ded898552b8bbfd2c2f925 172.25.254.30:6379slots:[10923-16383] (5461 slots) master1 additional replica(s)
M: c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea 172.25.254.10:6379slots:[0-5460] (5461 slots) master1 additional replica(s)
S: aee197141809a2f031f7e952d504c6aa9dd0c0c3 172.25.254.130:6379slots: (0 slots) slavereplicates 5614ce1e5d6c25524126130864b7eea815c373a0
S: b3f4291d1a2313d3a9907bf65e8287f488292c66 172.25.254.120:6379slots: (0 slots) slavereplicates c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea
S: adf52933b7434c129b81292b47103e6b1eab23fb 172.25.254.110:6379slots: (0 slots) slavereplicates f2a85df5b5355b3fd7ded898552b8bbfd2c2f925
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
How many slots do you want to move (from 1 to 16384)? 4096
What is the receiving node ID? c2ee7a506d8cc97b8f1b3b697d30aae90d51890a
Please enter all the source node IDs.Type 'all' to use all the nodes as source nodes for the hash slots.Type 'done' once you entered all the source nodes IDs.
Source node #1: all#添加salve
[root@redis-node2 ~]# redis-cli -a 123456 --cluster add-node 172.25.254.150:6379 172.25.254.20:6379  --cluster-slave --cluster-master-id  5614ce1e5d6c25524126130864b7eea815c373a0#查看集群信息
[root@redis-node2 ~]# redis-cli -a 123456 --cluster check 172.25.254.20:6379          Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
172.25.254.20:6379 (5614ce1e...) -> 0 keys | 4096 slots | 1 slaves.
172.25.254.50:6379 (c2ee7a50...) -> 1 keys | 4096 slots | 1 slaves.
172.25.254.30:6379 (f2a85df5...) -> 0 keys | 4096 slots | 1 slaves.
172.25.254.10:6379 (c0b144b6...) -> 0 keys | 4096 slots | 1 slaves.
[OK] 1 keys in 4 masters.
0.00 keys per slot on average.
>>> Performing Cluster Check (using node 172.25.254.20:6379)
M: 5614ce1e5d6c25524126130864b7eea815c373a0 172.25.254.20:6379slots:[6827-10922] (4096 slots) master1 additional replica(s)
S: 4325081cf2646880c6848decfda9a87f01068e97 172.25.254.150:6379slots: (0 slots) slavereplicates c2ee7a506d8cc97b8f1b3b697d30aae90d51890a
M: c2ee7a506d8cc97b8f1b3b697d30aae90d51890a 172.25.254.50:6379slots:[0-1364],[5461-6826],[10923-12287] (4096 slots) master1 additional replica(s)
M: f2a85df5b5355b3fd7ded898552b8bbfd2c2f925 172.25.254.30:6379slots:[12288-16383] (4096 slots) master1 additional replica(s)
M: c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea 172.25.254.10:6379slots:[1365-5460] (4096 slots) master1 additional replica(s)
S: aee197141809a2f031f7e952d504c6aa9dd0c0c3 172.25.254.130:6379slots: (0 slots) slavereplicates 5614ce1e5d6c25524126130864b7eea815c373a0
S: b3f4291d1a2313d3a9907bf65e8287f488292c66 172.25.254.120:6379slots: (0 slots) slavereplicates c0b144b6e29ea811040dd9e67a5b6ea8b8a1f5ea
S: adf52933b7434c129b81292b47103e6b1eab23fb 172.25.254.110:6379slots: (0 slots) slavereplicates f2a85df5b5355b3fd7ded898552b8bbfd2c2f925
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.

#clave節(jié)點(diǎn)沒有數(shù)據(jù)，可以直接刪除
[root@redis-node2 ~]# redis-cli  -a 123456 --cluster del-node 172.25.254.150:6379  4325081cf2646880c6848decfda9a87f01068e97#移除要下線主機(jī)的哈希槽位（master節(jié)點(diǎn)上）
[root@redis-node2 ~]# redis-cli -a 123456 --cluster reshard 172.25.254.20:6379 
How many slots do you want to move (from 1 to 16384)? 4096
What is the receiving node ID? 5614ce1e5d6c25524126130864b7eea815c373a0
Please enter all the source node IDs.Type 'all' to use all the nodes as source nodes for the hash slots.Type 'done' once you entered all the source nodes IDs.
Source node #1: c2ee7a506d8cc97b8f1b3b697d30aae90d51890a #移除節(jié)點(diǎn)的id
Source node #2: done[root@redis-node2 ~]# redis-cli  -a 123456 --cluster del-node 172.25.254.50:6379 c2ee7a506d8cc97b8f1b3b697d30aae90d51890a #再刪除節(jié)點(diǎn)