Redis 主从同步+哨兵
简介
通过使用 Redis 自带“主从同步+哨兵守护”功能提高Redis稳定性。
主从同步：保障数据主从数据实时同步。
哨兵：实时监控主redis如果故障，将从redis作为主使用。
环境：
- 系统：Centos7/Redhat7
- 服务：Redis4.0.11
- 服务器台数：1台（可多台）
- Redis服务数量：3个
- 192.168.1.100:6381（主）
- 192.168.1.100:6382（从）
- 192.168.1.100:6383（从）
Redis 主从同步
一、Redis主从同步搭建
1、解压缩包
tar -zxvf redis-4.0.11.tar.gz
2、移动到指定目录
mv redis-4.0.11 /usr/local/redis
3、移动到指定目录并编译安装
cd /usr/local/redis
make && make install
4、为每个Redis创建各自的目录
mkdir -p /usr/local/redis-ms/6381
mkdir -p /usr/local/redis-ms/6382
mkdir -p /usr/local/redis-ms/6383
5、将配置文件复制到创建目录下
cp /usr/local/redis/redis.conf /usr/local/redis-ms/6381/
cp /usr/local/redis/redis.conf /usr/local/redis-ms/6382/
cp /usr/local/redis/redis.conf /usr/local/redis-ms/6383/
6、redis 6381主 ：修改如下配置参数
vim /usr/local/redis-ms/6381/redis.conf
# 任意ip都可以连接
bind 0.0.0.0
# 关闭保护，允许非本地连接
protected-mode no
# 端口号
port 6381
# 后台运行
daemonize yes
# 开启日志形式
appendonly yes
# 进程守护文件，就是存放该进程号相关信息的地方
pidfile "/var/run/redis_6381.pid"
# db等相关目录位置
dir /usr/local/redis-ms/6381/
# 缓存库数量
databases 50
# 设置redis密码
requirepass ""
# 设置主从复制密码
masterauth ""
7、redis 6382从 ：修改如下配置参数
vim /usr/local/redis-ms/6382/redis.conf
# 任意ip都可以连接
bind 0.0.0.0
# 关闭保护，允许非本地连接
protected-mode no
# 端口号
port 6382
# 后台运行
daemonize yes
# 开启日志形式
appendonly yes
# 进程守护文件，就是存放该进程号相关信息的地方
pidfile "/var/run/redis_6382.pid"
# db等相关目录位置
dir /usr/local/redis-ms/6382/
# 缓存库数量
databases 50
# 设置redis密码
requirepass ""
# 设置主从复制密码
masterauth ""
# 主信息
slaveof 192.168.1.100 6381
8、redis 6383从 ：修改如下配置参数
vim /usr/local/redis-ms/6383/redis.conf
# 任意ip都可以连接
bind 0.0.0.0
# 关闭保护，允许非本地连接
protected-mode no
# 端口号
port 6383
# 后台运行
daemonize yes
# 开启日志形式
appendonly yes
# 进程守护文件，就是存放该进程号相关信息的地方
pidfile "/var/run/redis_6383.pid"
# db等相关目录位置
dir /usr/local/redis-ms/6383/
# 缓存库数量
databases 50
# 设置redis密码
requirepass ""
# 设置主从复制密码
masterauth ""
# 主信息
slaveof 192.168.1.100 6381
9、启动
/usr/local/redis/src/redis-server /usr/local/redis-ms/6381/redis.conf
/usr/local/redis/src/redis-server /usr/local/redis-ms/6382/redis.conf
/usr/local/redis/src/redis-server /usr/local/redis-ms/6383/redis.conf
二、测试Redis主从同步
1、查看主从同步状态
/usr/local/redis/src/redis-cli -p 6381 -a 123456 info
# Server
redis_version:4.0.11
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:c471ec760376b22e
redis_mode:standalone
os:Linux 3.10.0-123.el7.x86_64 x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:4.8.2
process_id:2788
run_id:3e7540f2dbcf55921c4e6bf5ac6de8f0c0d48625
tcp_port:6381
uptime_in_seconds:3196
uptime_in_days:0
hz:10
lru_clock:15365847
executable:/usr/local/redis/src/redis-server
config_file:/usr/local/redis-ms/6381/redis.conf # Clients
connected_clients:3
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0 # Memory
used_memory:1960456
used_memory_human:1.87M
used_memory_rss:10055680
used_memory_rss_human:9.59M
used_memory_peak:2001448
used_memory_peak_human:1.91M
used_memory_peak_perc:97.95%
used_memory_overhead:1935516
used_memory_startup:786632
used_memory_dataset:24940
used_memory_dataset_perc:2.12%
total_system_memory:499048448
total_system_memory_human:475.93M
used_memory_lua:37888
used_memory_lua_human:37.00K
maxmemory:0
maxmemory_human:0B
maxmemory_policy:noeviction
mem_fragmentation_ratio:5.13
mem_allocator:jemalloc-4.0.3
active_defrag_running:0
lazyfree_pending_objects:0 # Persistence
loading:0
rdb_changes_since_last_save:0
rdb_bgsave_in_progress:0
rdb_last_save_time:1575644640
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:0
rdb_current_bgsave_time_sec:-1
rdb_last_cow_size:6475776
aof_enabled:1
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:1
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok
aof_last_cow_size:8507392
aof_current_size:113
aof_base_size:58
aof_pending_rewrite:0
aof_buffer_length:0
aof_rewrite_buffer_length:0
aof_pending_bio_fsync:0
aof_delayed_fsync:0 # Stats
total_connections_received:17
total_commands_processed:8041
instantaneous_ops_per_sec:2
total_net_input_bytes:402231
total_net_output_bytes:1561243
instantaneous_input_kbps:0.14
instantaneous_output_kbps:0.18
rejected_connections:0
sync_full:0
sync_partial_ok:1
sync_partial_err:0
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:1
keyspace_misses:0
pubsub_channels:1
pubsub_patterns:0
latest_fork_usec:1179
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0 # Replication
role:master
connected_slaves:1
slave0:ip=192.168.1.100,port=6383,state=online,offset=224730,lag=1
master_replid:ca1e338e226a084983510088b89c15c556e7a945
master_replid2:f5f36c27bd86377158a1f2e85064f55924601b00
master_repl_offset:224871
second_repl_offset:22486
repl_backlog_active:1
repl_backlog_size:1048576
repl_backlog_first_byte_offset:1
repl_backlog_histlen:224871 # CPU
used_cpu_sys:2.09
used_cpu_user:1.02
used_cpu_sys_children:0.13
used_cpu_user_children:0.00 # Cluster
cluster_enabled:0 # Keyspace
db0:keys=1,expires=0,avg_ttl=0
redis状态
/usr/local/redis/src/redis-cli -p 6382 -a 123456 info
# Server
redis_version:4.0.11
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:c471ec760376b22e
redis_mode:standalone
os:Linux 3.10.0-123.el7.x86_64 x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:4.8.2
process_id:2958
run_id:7907851a00ca97feba2e43c82112dda4ca8ba9b2
tcp_port:6382
uptime_in_seconds:70
uptime_in_days:0
hz:10
lru_clock:15366134
executable:/usr/local/redis/src/redis-server
config_file:/usr/local/redis-ms/6382/redis.conf # Clients
connected_clients:4
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0 # Memory
used_memory:1960496
used_memory_human:1.87M
used_memory_rss:10022912
used_memory_rss_human:9.56M
used_memory_peak:2042400
used_memory_peak_human:1.95M
used_memory_peak_perc:95.99%
used_memory_overhead:1935516
used_memory_startup:786632
used_memory_dataset:24980
used_memory_dataset_perc:2.13%
total_system_memory:499048448
total_system_memory_human:475.93M
used_memory_lua:37888
used_memory_lua_human:37.00K
maxmemory:0
maxmemory_human:0B
maxmemory_policy:noeviction
mem_fragmentation_ratio:5.11
mem_allocator:jemalloc-4.0.3
active_defrag_running:0
lazyfree_pending_objects:0 # Persistence
loading:0
rdb_changes_since_last_save:1
rdb_bgsave_in_progress:0
rdb_last_save_time:1575647152
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:-1
rdb_current_bgsave_time_sec:-1
rdb_last_cow_size:0
aof_enabled:1
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:0
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok
aof_last_cow_size:8495104
aof_current_size:55
aof_base_size:55
aof_pending_rewrite:0
aof_buffer_length:0
aof_rewrite_buffer_length:0
aof_pending_bio_fsync:0
aof_delayed_fsync:0 # Stats
total_connections_received:5
total_commands_processed:161
instantaneous_ops_per_sec:2
total_net_input_bytes:11283
total_net_output_bytes:44463
instantaneous_input_kbps:0.19
instantaneous_output_kbps:0.23
rejected_connections:0
sync_full:0
sync_partial_ok:0
sync_partial_err:0
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:0
keyspace_misses:0
pubsub_channels:1
pubsub_patterns:0
latest_fork_usec:806
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0 # Replication
role:slave
master_host:192.168.1.100
master_port:6381
master_link_status:up
master_last_io_seconds_ago:0
master_sync_in_progress:0
slave_repl_offset:4901
slave_priority:100
slave_read_only:1
connected_slaves:0
master_replid:cdfb2756fa43e1d4dfce72986be98de38911dd38
master_replid2:0000000000000000000000000000000000000000
master_repl_offset:4901
second_repl_offset:-1
repl_backlog_active:1
repl_backlog_size:1048576
repl_backlog_first_byte_offset:1
repl_backlog_histlen:4901 # CPU
used_cpu_sys:0.05
used_cpu_user:0.01
used_cpu_sys_children:0.02
used_cpu_user_children:0.00 # Cluster
cluster_enabled:0 # Keyspace
db0:keys=1,expires=0,avg_ttl=0
redis状态
/usr/local/redis/src/redis-cli -p 6383 -a 123456 info
# Server
redis_version:4.0.11
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:c471ec760376b22e
redis_mode:standalone
os:Linux 3.10.0-123.el7.x86_64 x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:4.8.2
process_id:2966
run_id:e345097b352029bbe43aeea0ed17a7c7c305ba90
tcp_port:6383
uptime_in_seconds:115
uptime_in_days:0
hz:10
lru_clock:15366180
executable:/usr/local/redis/src/redis-server
config_file:/usr/local/redis-ms/6383/redis.conf # Clients
connected_clients:4
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0 # Memory
used_memory:1960480
used_memory_human:1.87M
used_memory_rss:10027008
used_memory_rss_human:9.56M
used_memory_peak:1980560
used_memory_peak_human:1.89M
used_memory_peak_perc:98.99%
used_memory_overhead:1935516
used_memory_startup:786632
used_memory_dataset:24964
used_memory_dataset_perc:2.13%
total_system_memory:499048448
total_system_memory_human:475.93M
used_memory_lua:37888
used_memory_lua_human:37.00K
maxmemory:0
maxmemory_human:0B
maxmemory_policy:noeviction
mem_fragmentation_ratio:5.11
mem_allocator:jemalloc-4.0.3
active_defrag_running:0
lazyfree_pending_objects:0 # Persistence
loading:0
rdb_changes_since_last_save:1
rdb_bgsave_in_progress:0
rdb_last_save_time:1575647153
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:-1
rdb_current_bgsave_time_sec:-1
rdb_last_cow_size:0
aof_enabled:1
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:0
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok
aof_last_cow_size:6397952
aof_current_size:55
aof_base_size:55
aof_pending_rewrite:0
aof_buffer_length:0
aof_rewrite_buffer_length:0
aof_pending_bio_fsync:0
aof_delayed_fsync:0 # Stats
total_connections_received:4
total_commands_processed:257
instantaneous_ops_per_sec:0
total_net_input_bytes:18203
total_net_output_bytes:65296
instantaneous_input_kbps:0.01
instantaneous_output_kbps:0.03
rejected_connections:0
sync_full:0
sync_partial_ok:0
sync_partial_err:0
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:0
keyspace_misses:0
pubsub_channels:1
pubsub_patterns:0
latest_fork_usec:933
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0 # Replication
role:slave
master_host:192.168.1.100
master_port:6381
master_link_status:up
master_last_io_seconds_ago:1
master_sync_in_progress:0
slave_repl_offset:8073
slave_priority:100
slave_read_only:1
connected_slaves:0
master_replid:cdfb2756fa43e1d4dfce72986be98de38911dd38
master_replid2:0000000000000000000000000000000000000000
master_repl_offset:8073
second_repl_offset:-1
repl_backlog_active:1
repl_backlog_size:1048576
repl_backlog_first_byte_offset:1
repl_backlog_histlen:8073 # CPU
used_cpu_sys:0.12
used_cpu_user:0.01
used_cpu_sys_children:0.01
used_cpu_user_children:0.00 # Cluster
cluster_enabled:0 # Keyspace
db0:keys=1,expires=0,avg_ttl=0
redis状态
2、进入主终端创建key
/usr/local/redis/src/redis-cli -p 6381 -a 123456 --raw
127.0.0.1:6381> set name 'xsk'
127.0.0.1:6381> get name
xsk
3、进入从终端查看同步状态
/usr/local/redis/src/redis-cli -p 6382 -a 123456 --raw
127.0.0.1:6381> get name
xsk
三、添加到系统服务
1、创建redis启动脚本存放目录
mkdir /usr/local/redis-ms/script
cd /usr/local/redis-ms/script/
2、创建启动脚本
vim ./start.sh
#!/bin/sh
/usr/local/redis/src/redis-server /usr/local/redis-ms/6381/redis.conf
/usr/local/redis/src/redis-server /usr/local/redis-ms/6382/redis.conf
/usr/local/redis/src/redis-server /usr/local/redis-ms/6383/redis.conf
3、创建停止脚本
vim ./stop.sh
#!/bin/sh
/usr/local/redis/src/redis-cli -p 6381 shutdown
/usr/local/redis/src/redis-cli -p 6382 shutdown
/usr/local/redis/src/redis-cli -p 6383 shutdown
4、创建重启脚本
vim ./restart.sh
#!/bin/sh
systemctl stop redis-ms
systemctl start redis-ms
5、赋值脚本权限
chmod 755 ./*
6、编写系统服务管理文件
vim /usr/lib/systemd/system/redis-ms.service
[Unit]
Description=redis-ms
After=network.target remote-fs.target nss-lookup.target
[Service]
Type=forking
ExecStart=/usr/local/redis-ms/script/start.sh
ExecStop=/usr/local/redis-ms/script/stop.sh
ExecReload=/usr/local/redis-ms/script/restart.sh
[Install]
WantedBy=multi-user.target
7、赋值权限
chmod 755 /usr/lib/systemd/system/redis-ms.service
8、重启服务并设置开机自启动
systemctl daemon-reload
systemctl enable redis-ms.service
systemctl restart redis-ms.service
Redis 哨兵
一、搭建哨兵
1、修改sentinel文件
vim /usr/local/redis/sentinel.conf
# 开启保护模式
protected-mode yes
# 任意IP都可链接
bind 0.0.0.0
# mymaster是Master的名称，192.168.0.100是Master的Ip。
# 1表示确认一个Master为O_DOWN最少需要多少个哨兵认可。
sentinel monitor mymaster 192.168.1.100 6381 1
# redis有登陆密码的话必须配置这项参数，设置密码
sentinel auth-pass mymaster 123456
# （默认30秒）指定Sentinel判定Master断线的时间。（单位为毫秒，判定为主观下线SDOWN）
sentinel down-after-milliseconds mymaster 10000
sentinel config-epoch redismaster 3
sentinel leader-epoch redismaster 3
2、启动
/usr/local/redis/src/redis-sentinel /usr/local/redis/sentinel.conf
二、添加系统服务
1、在执行脚本最下行添加命令
vim /usr/local/redis-ms/script/stop.sh
ps -aux | grep sentine |grep -v grep|awk '{print $2}'| xargs -I {} kill -9 {}
2、在执行脚本最下行添加命令
vim /usr/local/redis-ms/script/start.sh
nohup /usr/local/redis/src/redis-sentinel /usr/local/redis/sentinel.conf &
3、重启redis服务
systemctl daemon-reload
systemctl restart redis-ms.service
三、测试切换
1、关闭master后slave成为master
_._
_.-``__ ''-._
_.-`` `. `_. ''-._ Redis 4.0.11 (00000000/0) 64 bit
.-`` .-```. ```\/ _.,_ ''-._
( ' , .-` | `, ) Running in sentinel mode
|`-._`-...-` __...-.``-._|'` _.-'| Port: 26381
| `-._ `._ / _.-' | PID: 3032
`-._ `-._ `-./ _.-' _.-'
|`-._`-._ `-.__.-' _.-'_.-'|
| `-._`-._ _.-'_.-' | http://redis.io
`-._ `-._`-.__.-'_.-' _.-'
|`-._`-._ `-.__.-' _.-'_.-'|
| `-._`-._ _.-'_.-' |
`-._ `-._`-.__.-'_.-' _.-'
`-._ `-.__.-' _.-'
`-._ _.-'
`-.__.-' 3032:X 07 Dec 00:20:49.244 # WARNING: The TCP backlog setting of 511 cannot be enforced because /proc/sys/net/core/somaxconn is set to the lower value of 128.
3032:X 07 Dec 00:20:49.244 # Sentinel ID is 4df58ef409ac6b52991173453736d113bd337f19
3032:X 07 Dec 00:20:49.244 # +monitor master mymaster 192.168.1.100 6381 quorum 1 3032:X 07 Dec 00:22:09.709 # +sdown master mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:09.709 # +odown master mymaster 192.168.1.100 6381 #quorum 1/1
3032:X 07 Dec 00:22:09.709 # +new-epoch 8
3032:X 07 Dec 00:22:09.709 # +try-failover master mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:09.710 # +vote-for-leader 4df58ef409ac6b52991173453736d113bd337f19 8
3032:X 07 Dec 00:22:09.710 # +elected-leader master mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:09.710 # +failover-state-select-slave master mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:09.811 # +selected-slave slave 192.168.1.100:6382 192.168.1.100 6382 @ mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:09.811 * +failover-state-send-slaveof-noone slave 192.168.1.100:6382 192.168.1.100 6382 @ mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:09.878 * +failover-state-wait-promotion slave 192.168.1.100:6382 192.168.1.100 6382 @ mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:10.585 # +promoted-slave slave 192.168.1.100:6382 192.168.1.100 6382 @ mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:10.585 # +failover-state-reconf-slaves master mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:10.661 * +slave-reconf-sent slave 192.168.1.100:6383 192.168.1.100 6383 @ mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:11.624 * +slave-reconf-inprog slave 192.168.1.100:6383 192.168.1.100 6383 @ mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:11.625 * +slave-reconf-done slave 192.168.1.100:6383 192.168.1.100 6383 @ mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:11.676 # +failover-end master mymaster 192.168.1.100 6381
3032:X 07 Dec 00:22:11.676 # +switch-master mymaster 192.168.1.100 6381 192.168.1.100 6382
3032:X 07 Dec 00:22:11.676 * +slave slave 192.168.1.100:6383 192.168.1.100 6383 @ mymaster 192.168.1.100 6382
3032:X 07 Dec 00:22:11.676 * +slave slave 192.168.1.100:6381 192.168.1.100 6381 @ mymaster 192.168.1.100 6382
3032:X 07 Dec 00:22:21.696 # +sdown slave 192.168.1.100:6381 192.168.1.100 6381 @ mymaster 192.168.1.100 6382
日志
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