hbase扩容缩容

青旅半醒 2023-05-29 05:25 17阅读 0赞

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![在这里插入图片描述][20200515113638671.jpg_pic_center]

# 初始化集群 #

初始化集群：hadoop三个DataNode，HBASE集群只有一个regionserver。  
后面我们不停服的情况下，动态添加一个机器node4，在node4上启动Hregionserver服务。

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70]

# hbase动态扩容 #

# 配置regionservers #

配置`每台`机器的regionservers，添加node4:

[root@node1 conf]# cat regionservers 
    node3
    node4

这一步不是必须的，但是为了更好的维护集群，在master上进行一些ssh相关操作，最好执行这一步。

# 在node4上启动regionserver #

[root@node4 bin]# ./hbase-daemon.sh start regionserver
    running regionserver, logging to /data/program/hbase-2.1.5/bin/../logs/hbase-root-regionserver-node4.out
    [root@node4 bin]# jps
    2148 HRegionServer
    1910 DataNode
    2422 Jps

# 开启自动负载均衡balance #

先`balancer_enabled`看一下是自动负载均衡状态，如果是关闭的，则开启。  
在node4机器上开启负载均衡。命令：

hbase(main):017:0> balance_switch true
    Previous balancer state : false                                                                                                                                                                                                                                               
    Took 0.0262 seconds                                                                                                                                                                                                                                                           
    => "false"
    hbase(main):018:0> balancer_enabled
    true                                                                                                                                                                                                                                                                          
    Took 0.0232 seconds                                                                                                                                                                                                                                                           
    => true

> 注意不要用`balance_switch status`这个命令，balance\_switch status 经测试, 这个命令的意思是将balance状态强制转换为false, 无论之前是true还是false, 返回的是之前的状态, 所以一会儿true, 一会儿false, 所以这个命令很鸡肋, 别乱用, 查看当前状态的命令是balancer\_enabled

## 自动balance存在的问题及解决方案 ##

上述自动balance比较简单，但是存在严重的问题：`在中小集群上，会存在很多region同时处于离线状态，因此对HBASE集群整体可用性造成比较大的影响。`

region迁移过程中会出现RIT：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 1]  
为了解决上述问题，我们最好禁用自动balance，`手动迁移region`。

在没有开启自动负载均衡，但是开启了node4的regionserver时，这个regionserver会添加到集群中，但是region数量是0  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 2]

我们现在将node3节点的regionserver上的部分region手动迁移到node4。  
先看一下node3节点的regionserver上的region：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 3]  
可以看到有很多region，上面红线标识的就是regionID。

hbase(main):009:0> move '369a74e128cebe5765745aa6f1c2bd0b','node4,16020,1572921608641'
    Took 1.9108 seconds
    hbase(main):010:0> move '8dba2021c05515b03764f12bb2df1263','node4,16020,1572921608641'
    Took 2.1796 seconds

我们随机选了两个region迁移到node4上后：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 4]  
由于region比较多，可以写脚本去实现。

> 注意：迁移到新机器的region本地化率为0%，并且缓存中没有数据，所以发送到改节点的请求耗时会比较多，过一会等缓存中有数据了就好了。

我们将20个region迁移到node4后，看看node3和node4的本地化率情况：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 5]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 6]  
我们可以使用压缩来提高本地化率。

关于压缩请参考笔者博客

# hbase动态缩容 #

这里我们把node3下掉。

## 停止node3:`graceful_stop` ##

[root@node3 bin]# ./graceful_stop.sh node3
    2019-11-04T18:33:20 Disabling load balancer
    2019-11-04 18:33:35,579 WARN  [main] util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
    2019-11-04T18:33:39 Previous balancer state was true
    2019-11-04T18:33:39 Unloading node3 region(s)
    2019-11-04 18:33:40,608 WARN  [main] util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
    2019-11-04 18:33:41,542 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:zookeeper.version=3.4.10-39d3a4f269333c922ed3db283be479f9deacaa0f, built on 03/23/2017 10:13 GMT
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:host.name=node3
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:java.version=1.8.0_91
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:java.vendor=Oracle Corporation
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:java.home=/data/program/jdk1.8.0_91/jre
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: data/program/hbase-2.1.5/bin/../lib/spymemcached-2.12.2.jar:/data/program/hbase-2.1.5/bin/../lib/validation-api-1.1.0.Final.jar:/data/program/hbase-2.1.5/bin/../lib/xmlenc-0.52.jar:/data/program/hbase-2.1.5/bin/../lib/xz-1.0.jar:/data/program/hbase-2.1.5/bin/../lib/zookeeper-3.4.10.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/audience-annotations-0.5.0.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/commons-logging-1.2.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/findbugs-annotations-1.3.9-1.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/htrace-core4-4.2.0-incubating.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/log4j-1.2.17.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/slf4j-api-1.7.25.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/htrace-core-3.1.0-incubating.jar:/data/program/hbase-2.1.5/bin/../lib/client-facing-thirdparty/slf4j-log4j12-1.7.25.jar
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:java.library.path=/usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:java.io.tmpdir=/tmp
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:java.compiler=<NA>
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:os.name=Linux
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:os.arch=amd64
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:os.version=3.10.0-693.el7.x86_64
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:user.name=root
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:user.home=/root
    2019-11-04 18:33:41,543 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Client environment:user.dir=/data/program/hbase-2.1.5/bin
    2019-11-04 18:33:41,546 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Initiating client connection, connectString=node1:2181,node2:2181,node3:2181 sessionTimeout=3600000 watcher=org.apache.hadoop.hbase.zookeeper.ReadOnlyZKClient$$Lambda$13/451125583@368e3ff3
    2019-11-04 18:33:41,622 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb-SendThread(node3:2181)] zookeeper.ClientCnxn: Opening socket connection to server node3/192.168.229.102:2181. Will not attempt to authenticate using SASL (unknown error)
    2019-11-04 18:33:41,627 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb-SendThread(node3:2181)] zookeeper.ClientCnxn: Socket connection established to node3/192.168.229.102:2181, initiating session
    2019-11-04 18:33:41,661 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb-SendThread(node3:2181)] zookeeper.ClientCnxn: Session establishment complete on server node3/192.168.229.102:2181, sessionid = 0x36e35baf9fb002f, negotiated timeout = 40000
    2019-11-04 18:33:42,898 INFO  [pool-2-thread-1] util.RegionMover: Moving 21 regions from node3 to 1 servers using 1 threads .Ack Mode:true
    2019-11-04 18:33:43,178 INFO  [pool-3-thread-1] util.RegionMover: Moving region:369a74e128cebe5765745aa6f1c2bd0b from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:33:45,015 INFO  [pool-3-thread-1] util.RegionMover: Moved Region PERSON,,1572523808553.369a74e128cebe5765745aa6f1c2bd0b. cost:2.103
    2019-11-04 18:33:45,034 INFO  [pool-3-thread-1] util.RegionMover: Moving region:1588230740 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:33:47,398 INFO  [pool-3-thread-1] util.RegionMover: Moved Region hbase:meta,,1.1588230740 cost:2.382
    2019-11-04 18:33:47,461 INFO  [pool-3-thread-1] util.RegionMover: Moving region:35c5536e6bb608c9e3387387216795c8 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:33:51,983 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.CATALOG,,1571994812282.35c5536e6bb608c9e3387387216795c8. cost:4.584
    2019-11-04 18:33:52,024 INFO  [pool-3-thread-1] util.RegionMover: Moving region:c0fe5d3e3dc972ade56f59550797c673 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:33:53,308 INFO  [pool-3-thread-1] util.RegionMover: Moved Region hbase:namespace,,1571994739459.c0fe5d3e3dc972ade56f59550797c673. cost:1.325
    2019-11-04 18:33:53,996 INFO  [pool-3-thread-1] util.RegionMover: Moving region:8dba2021c05515b03764f12bb2df1263 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:33:55,315 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x02\x00\x00\x00,1571994824933.8dba2021c05515b03764f12bb2df1263. cost:2.006
    2019-11-04 18:33:55,483 INFO  [pool-3-thread-1] util.RegionMover: Moving region:da0b0f537784cb19292fc0c6d508d7c4 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:33:56,819 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x03\x00\x00\x00,1571994824933.da0b0f537784cb19292fc0c6d508d7c4. cost:1.504
    2019-11-04 18:33:57,114 INFO  [pool-3-thread-1] util.RegionMover: Moving region:6c9cf401f80eed32e8e1f2e1ef201550 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:33:58,431 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x05\x00\x00\x00,1571994824933.6c9cf401f80eed32e8e1f2e1ef201550. cost:1.612
    2019-11-04 18:33:58,551 INFO  [pool-3-thread-1] util.RegionMover: Moving region:e7c9f1368ca8a9174f7e1cd629a39f59 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:00,020 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x06\x00\x00\x00,1571994824933.e7c9f1368ca8a9174f7e1cd629a39f59. cost:1.589
    2019-11-04 18:34:00,158 INFO  [pool-3-thread-1] util.RegionMover: Moving region:4c7548e9b198d9ec1e57cf4b517b1ebb from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:01,388 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x0A\x00\x00\x00,1571994824933.4c7548e9b198d9ec1e57cf4b517b1ebb. cost:1.368
    2019-11-04 18:34:01,480 INFO  [pool-3-thread-1] util.RegionMover: Moving region:514943bcb21714497d14dc281caa9fb2 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:02,758 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x0B\x00\x00\x00,1571994824933.514943bcb21714497d14dc281caa9fb2. cost:1.369
    2019-11-04 18:34:02,817 INFO  [pool-3-thread-1] util.RegionMover: Moving region:48371c940ea51ebbfd990c44add97c0f from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:04,132 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x0C\x00\x00\x00,1571994824933.48371c940ea51ebbfd990c44add97c0f. cost:1.374
    2019-11-04 18:34:04,201 INFO  [pool-3-thread-1] util.RegionMover: Moving region:3bf058f5853fcdf12d58b933ba96c2b9 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:05,469 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x0E\x00\x00\x00,1571994824933.3bf058f5853fcdf12d58b933ba96c2b9. cost:1.336
    2019-11-04 18:34:05,539 INFO  [pool-3-thread-1] util.RegionMover: Moving region:90608adb5077809a2897aaa38062fa75 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:07,767 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x10\x00\x00\x00,1571994824933.90608adb5077809a2897aaa38062fa75. cost:2.298
    2019-11-04 18:34:07,814 INFO  [pool-3-thread-1] util.RegionMover: Moving region:c9a703a28803089342896fd6581f65b0 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:09,038 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x13\x00\x00\x00,1571994824933.c9a703a28803089342896fd6581f65b0. cost:1.271
    2019-11-04 18:34:09,101 INFO  [pool-3-thread-1] util.RegionMover: Moving region:dae717d89104c02c006872e6ec32dd65 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:11,325 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x14\x00\x00\x00,1571994824933.dae717d89104c02c006872e6ec32dd65. cost:2.287
    2019-11-04 18:34:11,366 INFO  [pool-3-thread-1] util.RegionMover: Moving region:b61768d26982052eb2b106cc00c1dc85 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:12,620 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x16\x00\x00\x00,1571994824933.b61768d26982052eb2b106cc00c1dc85. cost:1.295
    2019-11-04 18:34:12,660 INFO  [pool-3-thread-1] util.RegionMover: Moving region:12aa3ec8ff9699de5543fa560e009630 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:14,904 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x17\x00\x00\x00,1571994824933.12aa3ec8ff9699de5543fa560e009630. cost:2.283
    2019-11-04 18:34:14,929 INFO  [pool-3-thread-1] util.RegionMover: Moving region:f07dd988da903ef56c19b80506bb104b from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:16,136 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x18\x00\x00\x00,1571994824933.f07dd988da903ef56c19b80506bb104b. cost:1.231
    2019-11-04 18:34:16,148 INFO  [pool-3-thread-1] util.RegionMover: Moving region:dc870483899b31d0fb45ab1f7c935f4a from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:17,371 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x1B\x00\x00\x00,1571994824933.dc870483899b31d0fb45ab1f7c935f4a. cost:1.235
    2019-11-04 18:34:17,374 INFO  [pool-3-thread-1] util.RegionMover: Moving region:326d415fab55f79d54fb061fff319d21 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:18,545 INFO  [pool-3-thread-1] util.RegionMover: Moved Region SYSTEM.LOG,\x1F\x00\x00\x00,1571994824933.326d415fab55f79d54fb061fff319d21. cost:1.174
    2019-11-04 18:34:18,561 INFO  [pool-3-thread-1] util.RegionMover: Moving region:e9f006fd022bb12bd653492127f24c53 from node3,16020,1572860544858 to node4,16020,1572861995536
    2019-11-04 18:34:19,771 INFO  [pool-3-thread-1] util.RegionMover: Moved Region hbase:rsgroup,,1571994742444.e9f006fd022bb12bd653492127f24c53. cost:1.226
    2019-11-04 18:34:19,773 INFO  [pool-2-thread-1] util.RegionMover: No Regions to move....Quitting now
    2019-11-04 18:34:19,796 INFO  [main] client.ConnectionImplementation: Closing master protocol: MasterService
    2019-11-04 18:34:19,844 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb] zookeeper.ZooKeeper: Session: 0x36e35baf9fb002f closed
    2019-11-04 18:34:19,846 INFO  [ReadOnlyZKClient-node1:2181,node2:2181,node3:2181@0x2ddc8ecb-EventThread] zookeeper.ClientCnxn: EventThread shut down for session: 0x36e35baf9fb002f
    2019-11-04T18:34:20 Unloaded node3 region(s)
    2019-11-04T18:34:20 Stopping regionserver on node3
    running regionserver, logging to /data/program/hbase-2.1.5/bin/../logs/hbase-root-regionserver-node3.out
    stopping regionserver.
    2019-11-04T18:34:21 Restoring balancer state to true

graceful\_stop命令支持以下语法，可以停止，重启regionserver，对于集群维护有很大帮助：

[root@node1 bin]# ./graceful_stop.sh
    Usage: graceful_stop.sh [--config <conf-dir>] [-e] [--restart [--reload]] [--thrift] [--rest]  [-nob |--nobalancer ] <hostname>
     thrift         If we should stop/start thrift before/after the hbase stop/start
     rest           If we should stop/start rest before/after the hbase stop/start
     restart        If we should restart after graceful stop
     reload         Move offloaded regions back on to the restarted server
     n|noack        Enable noAck mode in RegionMover. This is a best effort mode for moving regions
     maxthreads xx  Limit the number of threads used by the region mover. Default value is 1.
     movetimeout xx Timeout for moving regions. If regions are not moved by the timeout value,exit with error. Default value is INT_MAX.
     hostname       Hostname of server we are to stop
     e|failfast     Set -e so exit immediately if any command exits with non-zero status
     nob| nobalancer Do not manage balancer states. This is only used as optimization in rolling_restart.sh to avoid multiple calls to hbase shell

graceful\_stop做了那么几件事情：

*  停止负载均衡 Disabling load balancer
 *  迁移region
 *  停止regionserver`Stopping regionserver on node3`
 *  开启负载均衡

再次查看负载均衡状态：

hbase(main):036:0> balancer_enabled
    true                                                                                                                                                                                                                                                                          
    Took 0.0613 seconds                                                                                                                                                                                                                                                           
    => true

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 7]

region重启过程中，动态均衡会被关闭一段时间，此期间会显示警告：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9pdDAwNy5ibG9nLmNzZG4ubmV0_size_16_color_FFFFFF_t_70 8]

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