当一台主机master宕掉之后，他的从机会取代主机么？

查看集群状态

1. 127.0.0.1:6385> cluster nodes
   
2. c8ff33e8da5fd8ef821c65974dda304d2e3327f9 192.168.58.129:6382@16382 slave f6b1fd5e58df90782f602b484c2011d52fc3482d 0 1733220836918 1 connected
   
3. 6656947825a5aed22e4ce1818c1e743739219374 192.168.58.212:6386@16386 slave 437c0ffe1015fc8c7049cfeb0af05fee17e4b0a1 0 1733220835000 5 connected
   
4. 73b5567a02ee9f958f00324bf25bee5ce8eb23bc 192.168.58.130:6384@16384 slave e1dafb251016aeaa59edf64c4f7bb3d4639f560a 0 1733220834890 3 connected
   
5. f6b1fd5e58df90782f602b484c2011d52fc3482d 192.168.58.212:6385@16385 myself,master - 0 0 1 connected 0-5460
   
6. 437c0ffe1015fc8c7049cfeb0af05fee17e4b0a1 192.168.58.130:6383@16383 master - 0 1733220835395 5 connected 10923-16383
   
7. e1dafb251016aeaa59edf64c4f7bb3d4639f560a 192.168.58.129:6381@16381 master - 0 1733220836410 3 connected 5461-10922

复制代码

停掉主机6385

1. 127.0.0.1:6385> SHUTDOWN
   
2. 
   
3. (10.02s)
   
4. not connected>
   
5. not connected>
   
6. not connected>
   
7. not connected>

复制代码

使用redis-cli命令进入redis再次查看集群状态

1. 127.0.0.1:6382> info replication
   
2. # Replication
   
3. role:master
   
4. connected_slaves:0
   
5. master_failover_state:no-failover
   
6. master_replid:f292ca63e04db6e7717cc5067f408bf733963bb2
   
7. master_replid2:6ab6cdfeb1902aaa71279434c6b2c0e46d28a7f4
   
8. master_repl_offset:0
   
9. second_repl_offset:1
   
10. repl_backlog_active:0
    
11. repl_backlog_size:1048576
    
12. repl_backlog_first_byte_offset:0
    
13. repl_backlog_histlen:0
    
14. 127.0.0.1:6382> cluster nodes
    
15. 437c0ffe1015fc8c7049cfeb0af05fee17e4b0a1 192.168.58.130:6383@16383 master - 0 1733221855390 5 connected 10923-16383
    
16. f6b1fd5e58df90782f602b484c2011d52fc3482d 192.168.58.212:6385@16385 master,fail - 1733221087102 1733221084545 1 disconnected
    
17. 6656947825a5aed22e4ce1818c1e743739219374 192.168.58.212:6386@16386 slave 437c0ffe1015fc8c7049cfeb0af05fee17e4b0a1 0 1733221854869 5 connected
    
18. 73b5567a02ee9f958f00324bf25bee5ce8eb23bc 192.168.58.130:6384@16384 slave e1dafb251016aeaa59edf64c4f7bb3d4639f560a 0 1733221853318 3 connected
    
19. e1dafb251016aeaa59edf64c4f7bb3d4639f560a 192.168.58.129:6381@16381 master - 0 1733221855000 3 connected 5461-10922
    
20. c8ff33e8da5fd8ef821c65974dda304d2e3327f9 192.168.58.129:6382@16382 myself,master - 0 1733221854000 7 connected 0-5460

复制代码

6382成功上位成为主机

那么6385原主机恢复之后，是否会重新上位？

不会！
当前的集群状态：

1. 127.0.0.1:6382> cluster nodes
   
2. 437c0ffe1015fc8c7049cfeb0af05fee17e4b0a1 192.168.58.130:6383@16383 master - 0 1733221855390 5 connected 10923-16383
   
3. f6b1fd5e58df90782f602b484c2011d52fc3482d 192.168.58.212:6385@16385 master,fail - 1733221087102 1733221084545 1 disconnected
   
4. 6656947825a5aed22e4ce1818c1e743739219374 192.168.58.212:6386@16386 slave 437c0ffe1015fc8c7049cfeb0af05fee17e4b0a1 0 1733221854869 5 connected
   
5. 73b5567a02ee9f958f00324bf25bee5ce8eb23bc 192.168.58.130:6384@16384 slave e1dafb251016aeaa59edf64c4f7bb3d4639f560a 0 1733221853318 3 connected
   
6. e1dafb251016aeaa59edf64c4f7bb3d4639f560a 192.168.58.129:6381@16381 master - 0 1733221855000 3 connected 5461-10922
   
7. c8ff33e8da5fd8ef821c65974dda304d2e3327f9 192.168.58.129:6382@16382 myself,master - 0 1733221854000 7 connected 0-5460

复制代码

重新指定6385配置文件启动服务：

1. 127.0.0.1:6385> cluster nodes
   
2. 0a820807a70885c1d87d141824d3869dcf2418ee 192.168.58.130:6383@16383 master - 0 1733300452328 3 connected 5461-10922
   
3. 91cf395e8f04a5df1aeec4602dd38b3e4a708d55 192.168.58.130:6384@16384 slave ba40235fdad71fb36c3bf165ea51055825d453c2 0 1733300451285 1 connected
   
4. be191621d4aa881d864a113c385d58b751753392 192.168.58.212:6385@16385 myself,slave fedf4b13be2122f44dde749a08c4b943582b3566 0 0 7 connected
   
5. 30e5bdec200a671e4de666551d4489f0035235ba 192.168.58.212:6386@16386 slave 0a820807a70885c1d87d141824d3869dcf2418ee 0 1733300452892 3 connected
   
6. ba40235fdad71fb36c3bf165ea51055825d453c2 192.168.58.129:6381@16381 master - 0 1733300453572 1 connected 0-5460
   
7. fedf4b13be2122f44dde749a08c4b943582b3566 192.168.58.129:6382@16382 master - 0 1733300452659 7 connected 10923-16383

复制代码

节点主从调整

当前集群状态6385为从，6382为主

1. 127.0.0.1:6385> cluster nodes
   
2. 0a820807a70885c1d87d141824d3869dcf2418ee 192.168.58.130:6383@16383 master - 0 1733301081028 3 connected 5461-10922
   
3. 91cf395e8f04a5df1aeec4602dd38b3e4a708d55 192.168.58.130:6384@16384 slave ba40235fdad71fb36c3bf165ea51055825d453c2 0 1733301082183 1 connected
   
4. be191621d4aa881d864a113c385d58b751753392 192.168.58.212:6385@16385 myself,slave fedf4b13be2122f44dde749a08c4b943582b3566 0 0 7 connected
   
5. 30e5bdec200a671e4de666551d4489f0035235ba 192.168.58.212:6386@16386 slave 0a820807a70885c1d87d141824d3869dcf2418ee 0 1733301082954 3 connected
   
6. ba40235fdad71fb36c3bf165ea51055825d453c2 192.168.58.129:6381@16381 master - 0 1733301082057 1 connected 0-5460
   
7. fedf4b13be2122f44dde749a08c4b943582b3566 192.168.58.129:6382@16382 master - 0 1733301081260 7 connected 10923-16383

复制代码

执行命令cluster favlover ,主从节点调整，6385为主，6382为从

1. 127.0.0.1:6385> cluster nodes
   
2. 0a820807a70885c1d87d141824d3869dcf2418ee 192.168.58.130:6383@16383 master - 0 1733301262000 3 connected 5461-10922
   
3. 91cf395e8f04a5df1aeec4602dd38b3e4a708d55 192.168.58.130:6384@16384 slave ba40235fdad71fb36c3bf165ea51055825d453c2 0 1733301261585 1 connected
   
4. be191621d4aa881d864a113c385d58b751753392 192.168.58.212:6385@16385 myself,master - 0 0 8 connected 10923-16383
   
5. 30e5bdec200a671e4de666551d4489f0035235ba 192.168.58.212:6386@16386 slave 0a820807a70885c1d87d141824d3869dcf2418ee 0 1733301262869 3 connected
   
6. ba40235fdad71fb36c3bf165ea51055825d453c2 192.168.58.129:6381@16381 master - 0 1733301263074 1 connected 0-5460
   
7. fedf4b13be2122f44dde749a08c4b943582b3566 192.168.58.129:6382@16382 slave be191621d4aa881d864a113c385d58b751753392 0 1733301261700 8 connected

复制代码

命令补充

当主节点宕掉之后，从节点没有上位成为主机使用如下命令强制提升为主机

1. redis-cli -p 6382 cluster failover force

复制代码

从

1. 6382

复制代码

节点执行重新加入集群命令

1. redis-cli -a 111111 -p 6382 cluster meet 192.168.58.212 6385

复制代码

到此这篇关于Redis高阶之容错切换的实现的文章就介绍到这了,更多相关Redis 容错切换   内容请搜索脚本之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持脚本之家！

来源：https://www.jb51.net/database/336663gg9.htm
免责声明：如果侵犯了您的权益，请联系站长，我们会及时删除侵权内容，谢谢合作！