Redis主從復制、多實例及其高可用(三)--技術流ken
阿新 • • 發佈：2018-11-15
ups not run mct redis 監控 主從復制 傳輸 recv cep
Redis主從復制
Redis的主從復制策略是通過其持久化的rdb文件來實現的，其過程是先dump出rdb文件，將rdb文件全量傳輸給slave，然後再將dump後的操作實時同步到slave中。讓從服務器(slave server)成為主服務器(master server)的精確復制品。
Redis主從復制的實現
首先需要準備兩臺服務器，兩臺都要安裝redis程序
主服務器IP: 10.220.5.137
從服務器IP: 10.220.5.138
第一步：安裝redis（主從兩端都要操作）
[root@ken html]# yum install redis -y
第二步：啟動redis（主從兩端都要操作）
[root@ken html]# systemctl restart redis
第三步：修改配置文件（主從兩端都要操作）
大約在61行處，修改綁定的IP地址為本機IP
# 47 # bind 192.168.1.100 10.0.0.1 48 # bind 127.0.0.1 ::1 49 # 50 # ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the 51 # internet, binding to all the interfaces is dangerous and will expose the52 # instance to everybody on the internet. So by default we uncomment the 53 # following bind directive, that will force Redis to listen only into 54 # the IPv4 lookback interface address (this means Redis will be able to 55 # accept connections only from clients running into the same computer it56 # is running). 57 # 58 # IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES 59 # JUST COMMENT THE FOLLOWING LINE. 60 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 61 bind 10.220.5.137 62 63 # Protected mode is a layer of security protection, in order to avoid that 64 # Redis instances left open on the internet are accessed and exploited. 65 # 66 # When protected mode is on and if: 67 #
# bind 192.168.1.100 10.0.0.1 # bind 127.0.0.1 ::1 # # ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the # internet, binding to all the interfaces is dangerous and will expose the # instance to everybody on the internet. So by default we uncomment the # following bind directive, that will force Redis to listen only into # the IPv4 lookback interface address (this means Redis will be able to # accept connections only from clients running into the same computer it # is running). # # IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES # JUST COMMENT THE FOLLOWING LINE. # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ bind 10.220.5.138 # Protected mode is a layer of security protection, in order to avoid that # Redis instances left open on the internet are accessed and exploited. # # When protected mode is on and if: # # 1) The server is not binding explicitly to a set of addresses using the # "bind" directive. # 2) No password is configured.
第四步：重啟redis(主從兩端都要操作)
[root@ken html]# systemctl restart redis
第五步：登錄redis
修改了綁定的地址之後需要指定本機的IP地址才能登錄
[root@ken html]# redis-cli -h 10.220.5.138
第六步：實現主從復制
10.220.5.138:6379> SLAVEOF 10.220.5.137 6739 OK
第七步：查看
在主服務器端查看所有的key
10.220.5.137:6379> keys * 1) "gender" 2) "ken" 3) "tel" 4) "ad" 5) "kenken" 6) "name" 7) "myha" 8) "addr"
在從服務器端查看所有的key.可以看到已經復制過來了
10.220.5.138:6379> keys * 1) "name" 2) "ken" 3) "kenken" 4) "addr" 5) "myha" 6) "ad" 7) "tel" 8) "gender"
Redis的多實例
顧名思義多實例就是一臺服務器上安裝多個redis服務器，這樣可以更大程度的利用有限資源，在做一些實驗的時候也是強烈建議使用多實例的方式，以節省內存消耗。下面就來看一下如何實現多實例吧。
Redis實現多實例
第一步：創建目錄
準備在10.220.5.137服務器端創建三個實例6379 6380 6381
[root@ken ~]# mkdir /redis/{6379,6380,6381} -p
第二步:復制配置文件到三個目錄之下
[root@ken ~]# cp /etc/redis.conf /redis/6379/ [root@ken ~]# cp /etc/redis.conf /redis/6380/ [root@ken ~]# cp /etc/redis.conf /redis/6381/
第三步：修改每個目錄之下的配置文件
6379端口實例配置
[root@ken ~]# egrep -v ‘^#|^$‘ /redis/6379/redis.conf bind 10.220.5.137 protected-mode yes port 6379 tcp-backlog 511 timeout 0 tcp-keepalive 300 daemonize no supervised no pidfile /redis/6379/redis_6379.pid loglevel notice logfile /redis/6379/redis.log
...
6380端口實例配置
[root@ken ~]# egrep -v ‘^#|^$‘ /redis/6380/redis.conf bind 10.220.5.137 protected-mode yes port 6380 tcp-backlog 511 timeout 0 tcp-keepalive 300 daemonize no supervised no pidfile /redis/6380/redis_6379.pid loglevel notice logfile /redis/6380/redis.log databases 16 save 900 1 save 300 10 save 60 10000 ....
6381端口實例配置
[root@ken ~]# egrep -v ‘^#|^$‘ /redis/6381/redis.conf bind 10.220.5.137 protected-mode yes port 6381 tcp-backlog 511 timeout 0 tcp-keepalive 300 daemonize no supervised no pidfile /redis/6381/redis_6379.pid loglevel notice logfile /redis/6381/redis.log databases 16 save 900 1 save 300 10 save 60 10000 ....
第四步:啟動後臺運行
大約在128行處修改為yes,三個配置文件都需要修改
...
# By default Redis does not run as a daemon. Use ‘yes‘ if you need it. 127 # Note that Redis will write a pid file in /var/run/redis.pid when daemonized. 128 daemonize yes 129 130 # If you run Redis from upstart or systemd, Redis can interact with your 131 # supervision tree. Options:
...
第五步：啟動多實例
[root@ken ~]# redis-server /redis/6379/redis.conf [root@ken ~]# redis-server /redis/6380/redis.conf [root@ken ~]# redis-server /redis/6381/redis.conf [root@ken ~]# ss -tnl State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:10050 *:* LISTEN 0 128 10.220.5.137:6379 *:* LISTEN 0 128 10.220.5.137:6380 *:* LISTEN 0 128 10.220.5.137:6381 *:* LISTEN 0 128 *:111 *:* LISTEN 0 128 *:22 *:* LISTEN 0 128 :::10050 :::* LISTEN 0 128 :::111 :::* LISTEN 0 128 :::80 :::* LISTEN 0 128 :::22 :::*
至此多實例已經配置成功
Redis的高可用
redis高可用即主節點出現故障時，從節點會接替主節點，這個時候從節點就變成了主節點，實現redis的高可用。
接著上面配置好的多實例，現在我們來實現redis的高可用
主節點：10.220.5.137:6379
從1節點：10.220.5.137:6380
從2節點：10.220.5.138:6381
監控端：10.220.5.138
第一步：從節點指向主節點
從1節點
[root@ken ~]# redis-cli -h 10.220.5.137 -p 6380 10.220.5.137:6380> SLAVEOF 10.220.5.137 6379 OK 10.220.5.137:6380> exit
從2節點
[root@ken ~]# redis-cli -h 10.220.5.137 -p 6381 10.220.5.137:6381> SLAVEOF 10.220.5.137 6379 OK 10.220.5.137:6381> exit
第二步：在主節點查看
可以看到如下信息role為master.連接的slave端為2個
[root@ken ~]# redis-cli -h 10.220.5.137 -p 6379
10.220.5.137:6379> info replication # Replication role:master connected_slaves:2 slave0:ip=10.220.5.137,port=6380,state=online,offset=365,lag=0 slave1:ip=10.220.5.137,port=6381,state=online,offset=365,lag=1 master_repl_offset:365 repl_backlog_active:1 repl_backlog_size:1048576 repl_backlog_first_byte_offset:2 repl_backlog_histlen:364
第三步：修改監控端的配置文件
只需要修改17行關閉保護模式，以及69行處，添加主節點信息即可
[root@ken html]# vim /etc/redis-sentinel.conf
15 # bind 127.0.0.1 192.168.1.1
16 #
17 protected-mode no
18
19 # port <sentinel-port>
20 # The port that this sentinel instance will run on
21 port 26379
... 67 # Note: master name should not include special characters or spaces. 68 # The valid charset is A-z 0-9 and the three characters ".-_". 69 sentinel monitor mymaster 10.220.5.137 6379 1 70 71 # sentinel auth-pass <master-name> <password> 72 # ...
第四步：啟動監控節點
sentinel監控的是26379
[root@ken html]# systemctl restart redis-sentinel [root@ken html]# ss -tnl State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:10050 *:* LISTEN 0 128 *:26379 *:* LISTEN 0 128 10.220.5.138:6379 *:* LISTEN 0 128 *:111 *:* LISTEN 0 128 *:22 *:* LISTEN 0 128 :::10050 :::* LISTEN 0 128 :::26379 :::* LISTEN 0 128 :::111 :::* LISTEN 0 128 :::80 :::* LISTEN 0 128 :::22 :::*
第五步：登錄監控端
[root@ken html]# redis-cli -h 10.220.5.138 -p 26379
第六步：查看主服務端信息
現在可以看到主服務器端節點為10.220.5.137，端口號為6379
10.220.5.138:26379> sentinel masters 1) 1) "name" 2) "mymaster" 3) "ip" 4) "10.220.5.137" 5) "port" 6) "6379" 7) "runid" 8) "1096f9bef5606124ddd437f93e3c7d5027061abf" 9) "flags" 10) "master" 11) "link-pending-commands" 12) "0" 13) "link-refcount" 14) "1" 15) "last-ping-sent" 16) "0" ...
第七步：查看從服務器點狀態
這裏會看到所有的從節點信息
10.220.5.138:26379> sentinel slaves mymaster 1) 1) "name" 2) "10.220.5.137:6380" 3) "ip" 4) "10.220.5.137" 5) "port" 6) "6380" 7) "runid" 8) "bc8524006a66bfee2aaa15d3b5615fb0cdb50cb1" 9) "flags" 10) "slave" 11) "link-pending-commands" 12) "0" 13) "link-refcount" 14) "1" 15) "last-ping-sent" 16) "0" 17) "last-ok-ping-reply" 18) "521" 19) "last-ping-reply" 20) "521" 21) "down-after-milliseconds" 22) "30000" 23) "info-refresh" 24) "8370" 25) "role-reported" ...
Redis高可以用測試
第一步：關閉主服務器節點
[root@ken ~]# ps aux | grep redis root 4403 0.2 0.4 142952 2240 ? Rsl 20:50 0:01 redis-server 10.220.5.137:6379 root 4408 0.1 0.4 142952 2248 ? Ssl 20:50 0:01 redis-server 10.220.5.137:6380 root 4413 0.1 0.4 142952 2248 ? Ssl 20:50 0:01 redis-server 10.220.5.137:6381 root 4457 0.0 0.1 112704 968 pts/0 S+ 21:04 0:00 grep --color=auto redis [root@ken ~]# kill -9 4403 [root@ken ~]# ps aux | grep redis root 4408 0.1 0.4 142952 2264 ? Ssl 20:50 0:01 redis-server 10.220.5.137:6380 root 4413 0.1 0.4 142952 2264 ? Ssl 20:50 0:01 redis-server 10.220.5.137:6381 root 4459 0.0 0.1 112704 964 pts/0 R+ 21:04 0:00 grep --color=auto redis
第二步：在監控節點查看主服務器端節點狀態.
可以看到現在的主服務器節點已經變成10.220.5.137端口號為6380
10.220.5.138:26379> sentinel masters 1) 1) "name" 2) "mymaster" 3) "ip" 4) "10.220.5.137" 5) "port" 6) "6380" 7) "runid" 8) "bc8524006a66bfee2aaa15d3b5615fb0cdb50cb1" 9) "flags" 10) "master" 11) "link-pending-commands" 12) "0" 13) "link-refcount" 14) "1" 15) "last-ping-sent" 16) "0" 17) "last-ok-ping-reply" 18) "777" 19) "last-ping-reply" 20) "777" 21) "down-after-milliseconds" 22) "30000" 23) "info-refresh"
...
Redis主從復制、多實例及其高可用(三)--技術流ken