使用kafkat在线扩缩容kafkareplicas

本文档应用环境为 kafka-0.8.2.0, 其余版本请先行测试

场景

线上很多 kafka 的 topic 的副本数为1,这样的设置丧失了 kafka 高可用的特性,所以我们需要把 topic 的副本数至少设置为2(当前3台 kafka)

我们使用 kafkat 这个工具,这个工具是 ruby 写的,所以我们先安装 ruby 环境

参考 https://ruby-china.org/wiki/rvm-guide

这时候你应该已经由了 gem 命令

继续参考https://github.com/airbnb/kafkat 把 kafkat 装上, 并配置好你的 kafka 环境参数到 ~/.kafkatcfg

实操

我们修改 topic 的 replicas 为2

 
     
      
        
          [root 
          @ 
          001  
          kafka]# kafkat partitions IM_APP_BINSPECT_MSG_TOPIC 
         
 
          Topic       Partition   Leader      Replicas                        ISRs 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          0        
          2        
          [ 
          2 
          ]                         [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          1        
          3        
          [ 
          3 
          ]                         [ 
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          2        
          1        
          [ 
          1 
          ]                         [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          3        
          2        
          [ 
          2 
          ]                         [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          4        
          3        
          [ 
          3 
          ]                         [ 
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          5        
          1        
          [ 
          1 
          ]                         [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          6        
          2        
          [ 
          2 
          ]                         [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          7        
          3        
          [ 
          3 
          ]                         [ 
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          8        
          1        
          [ 
          1 
          ]                         [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          9        
          2        
          [ 
          2 
          ]                         [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          10       
          3        
          [ 
          3 
          ]                         [ 
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          11       
          1        
          [ 
          1 
          ]                         [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          12       
          2        
          [ 
          2 
          ]                         [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          13       
          3        
          [ 
          3 
          ]                         [ 
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          14       
          1        
          [ 
          1 
          ]                         [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          15       
          2        
          [ 
          2 
          ]                         [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          16       
          3        
          [ 
          3 
          ]                         [ 
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          17       
          1        
          [ 
          1 
          ]                         [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          18       
          2        
          [ 
          2 
          ]                         [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          19       
          3        
          [ 
          3 
          ]                         [ 
          3 
          ] 
         
 
          [root 
          @ 
          001  
          kafka]# kafkat set-replication-factor IM_APP_BINSPECT_MSG_TOPIC --newrf  
          2  
          --brokers  
          1 
          , 
          2 
          , 
          3 
         
 
          This operation executes the following assignments: 
         
 
          Topic       Partition   Replicas 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          0        
          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          1        
          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          2        
          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          3        
          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          4        
          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          5        
          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          6        
          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          7        
          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          8        
          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          9        
          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          10       
          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          11       
          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          12       
          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          13       
          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          14       
          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          15       
          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          16       
          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          17       
          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          18       
          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          19       
          [ 
          3 
          ,  
          2 
          ] 
         
 
          Proceed (y/n)? 
         
 
          y 
         
 
          Beginning. 
         
 
          Started. 
         
 
          [root 
          @ 
          001  
          kafka]# kafkat partitions IM_APP_BINSPECT_MSG_TOPIC 
         
 
          Topic       Partition   Leader      Replicas                        ISRs 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          0        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          1        
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          2        
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          3        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          4        
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          5        
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          6        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          7        
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          8        
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          9        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          10       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          11       
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          12       
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          13       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          14       
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          15       
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          16       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          17       
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          18       
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          19       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ] 
         
 
      
 
     
   

解释

上面一共执行了3个命令

kafkat partitions IM_APP_BINSPECT_MSG_TOPIC 查看 topic 的分区情况
kafkat set-replication-factor IM_APP_BINSPECT_MSG_TOPIC --newrf 2 --brokers 1,2,3 重新设置副本数为2 --newrf 2 , 你有几个 broker就在--brokers 后面指定
kafkat partitions IM_APP_BINSPECT_MSG_TOPIC 检查是否生效

根据 topic 数据量最后完成的时间也不同(大概几分钟)

这是最后的完成情况

 
     
      
        
          [root 
          @ 
           
          001  
          kafka]# kafkat partitions IM_APP_BINSPECT_MSG_TOPIC 
         
 
          Topic       Partition   Leader      Replicas                        ISRs 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          0        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          1        
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          2        
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          3        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          4        
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          5        
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          6        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          7        
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          8        
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          9        
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          10       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          11       
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          12       
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          13       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          14       
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          15       
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          16       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          17       
          1        
          [ 
          1 
          ,  
          3 
          ]                          [ 
          1 
          ,  
          3 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          18       
          2        
          [ 
          2 
          ,  
          1 
          ]                          [ 
          2 
          ,  
          1 
          ] 
         
 
          IM_APP_BINSPECT_MSG_TOPIC    
          19       
          3        
          [ 
          3 
          ,  
          2 
          ]                          [ 
          3 
          ,  
          2 
          ] 
         
 
      
 
     
   