Hbase无法给用户赋权，并报错。
问题背景描述：
测试环境，hdfs被format过。很多基于hdfs的环境都受到了影响。hbase也受到了影响。但是hbase在master启动的过程中，只要hdfs上有/hbase目录
建表之后，在赋权的时候，发现有错误
hbase(main):001:0> user_permission
User Namespace,Table,Family,Qualifier:Permission
ERROR: DISABLED: Security features are not available
hbase(main):001:0> grant 'test_user', 'RWXCA' , 'test_table'
ERROR: DISABLED: Security features are not available
Here is some help for this command:
Grant users specific rights.
Syntax : grant <user>, <permissions> [, <@namespace> [, <table> [, <column family> [, <column qualifier>]]]
hbase(main):002:0> hbase:acl
NoMethodError: undefined method `hbase' for #<Object:0x2a37210>2.以开始以为语法有错误，不会啊，很简单的语法。经过测试几个命令发现，但凡和权限相关的命令，都失败了
百度到一些建议，需要检查参数，在确认下面几个参数都设置正确的情况下，问题依旧
hbase.master.keytab.file
hbase.master.kerberos.principal
hbase.regionserver.keytab.file
hbase.regionserver.kerberos.principal
hbase.coprocessor.master.classes
hbase.coprocessor.region.classes
hbase.security.authorization3.百度到以下链接，其中有介绍：
参考链接
https://community.hortonworks.com/questions/50984/security-features-not-available-in-hbase-kerberize.html
It seems your hbase:acl table is not created.
can you check hbase-site.xml at master side as well it should have:-
<property>
<name>hbase.coprocessor.master.classes</name>
<value>org.apache.hadoop.hbase.security.access.AccessController</value>
</property>
try restarting your cluster as postStartMaster step should create this table, once you are able to do scan 'hbase:acl' , you will not see above error "ERROR: DISABLED:Security features are not available"4.下面这句话，提醒了我，是不是hbase:acl丢失了？
try restarting your cluster as postStartMaster step should create this table, once you are able to do scan 'hbase:acl'5.一检查，发现真没了
6.正常的情况应该是
7.问题原因找到了，开始找解决办法吧。继续百度（search技术文档，特别怀念google）
如何重建hbase:acl呢？安装过程中hbase并没有任何特殊设置，只要在hdfs上创建一个/hbase目录，启动hbase master就会自动创建需要的文件。为什么重启几次，都没有重新创建这个acl表呢？
查看hbase master log，可以看到错误“The table hbase:acl does not exist in meta but has a znode. run hbck to fix inconsistencies.” 通过命令hbase hbck检查，没有错误。问题也没有解决
2018-02-24 16:41:40,011 INFO [testserver:16000.activeMasterManager] master.HMaster: Master has completed initialization
2018-02-24 16:41:40,016 INFO [testserver:16000.activeMasterManager] quotas.MasterQuotaManager: Quota support disabled
2018-02-24 16:41:40,062 INFO [testserver:16000.activeMasterManager] master.HMaster: Client=null/null create 'hbase:acl', {NAME => 'l', DATA_BLOCK_ENCODING => 'NONE', BLOOMFILTER => 'NONE', REPLICATION_SCOPE => '0', COMPRESSION => 'NONE', VERSIONS => '1', TTL => 'FOREVER', MIN_VERSIONS => '0', CACHE_DATA_IN_L1 => 'true', KEEP_DELETED_CELLS => 'FALSE', BLOCKSIZE => '8192', IN_MEMORY => 'true', BLOCKCACHE => 'true'}
2018-02-24 16:41:40,200 WARN [ProcedureExecutorThread-1] procedure.CreateTableProcedure: The table hbase:acl does not exist in meta but has a znode. run hbck to fix inconsistencies.
2018-02-24 16:41:40,202 ERROR [testserver:16000.activeMasterManager] master.HMaster: Coprocessor postStartMaster() hook failed
org.apache.hadoop.hbase.TableExistsException: hbase:acl
at org.apache.hadoop.hbase.master.procedure.CreateTableProcedure.prepareCreate(CreateTableProcedure.java:300)
at org.apache.hadoop.hbase.master.procedure.CreateTableProcedure.executeFromState(CreateTableProcedure.java:107)
at org.apache.hadoop.hbase.master.procedure.CreateTableProcedure.executeFromState(CreateTableProcedure.java:58)
at org.apache.hadoop.hbase.procedure2.StateMachineProcedure.execute(StateMachineProcedure.java:107)
at org.apache.hadoop.hbase.procedure2.Procedure.doExecute(Procedure.java:427)
at org.apache.hadoop.hbase.procedure2.ProcedureExecutor.execProcedure(ProcedureExecutor.java:999)
at org.apache.hadoop.hbase.procedure2.ProcedureExecutor.execLoop(ProcedureExecutor.java:803)
at org.apache.hadoop.hbase.procedure2.ProcedureExecutor.execLoop(ProcedureExecutor.java:756)
at org.apache.hadoop.hbase.procedure2.ProcedureExecutor.access$200(ProcedureExecutor.java:75)
at org.apache.hadoop.hbase.procedure2.ProcedureExecutor$1.run(ProcedureExecutor.java:441)
2018-02-24 16:41:40,496 INFO [ProcedureExecutorThread-1] procedure2.ProcedureExecutor: Rolledback procedure CreateTableProcedure (table=hbase:acl) id=2 owner=hbase state=ROLLEDBACK exec-time=299msec exception=org.apache.hadoop.hbase.TableExistsException: hbase:acl
2018-02-24 16:46:05,790 INFO [LruBlockCacheStatsExecutor] hfile.LruBlockCache: totalSize=3.24 MB, freeSize=3.08 GB, max=3.08 GB, blockCount=0, accesses=0, hits=0, hitRatio=0, cachingAccesses=0, cachingHits=0, cachingHitsRatio=0,evictions=29, evicted=0, evictedPerRun=0.08.上面报错，既然已经明确说znode的问题，我们就去检查zookeeper上的情况吧。
确实看到，前面准备赋权，却失败的信息，记录在znode的acl路径下
hbase zkcli
[zk: 192.168.0.72:2181,192.168.0.73:2181,192.168.0.74:2181(CONNECTED) 3] ls /hbase
[meta-region-server, acl, backup-masters, table, draining, region-in-transition, running, table-lock, balancer, master, tokenauth, namespace, hbaseid, online-snapshot, replication, splitWAL, recovering-regions, rs, flush-table-proc]
[zk: 192.168.0.72:2181,192.168.0.73:2181,192.168.0.74:2181(CONNECTED) 4] ls /hbase/acl
[@test_user]9.在zk上删除/hbase的信息，然后重启hbase整个集群，让hbase自动重建acl表
[zk: 192.168.0.72:2181,192.168.0.73:2181,192.168.0.74:2181(CONNECTED) 6] rmr /hbase
[zk: 192.168.0.72:2181,192.168.0.73:2181,192.168.0.74:2181(CONNECTED) 7] ls /
[alert, kafka-manager-1.3.3.13, rmstore, yarn-leader-election, kafka10-dev2, livy, kafka10, kafka10-dev, dubbo, eos, alert_leader, election, DP, hadoop-ha, zookeeper, leader, user]
[zk: 192.168.0.72:2181,192.168.0.73:2181,192.168.0.74:2181(CONNECTED) 8] [hbase@testserver ~]$ exit10.可以看到，文件已经回来了
[hdfs@testserver ~]$ hdfs dfs -ls /hbase/data/hbase
Found 3 items
drwxrwx--- - hbase hadoop 0 2018-02-24 17:00 /hbase/data/hbase/acl
drwxrwx--- - hbase hadoop 0 2018-02-24 16:59 /hbase/data/hbase/meta
drwxrwx--- - hbase hadoop 0 2018-02-24 17:00 /hbase/data/hbase/namespace11.acl表也可以查看了
hbase(main):004:0> scan 'hbase:acl'
ROW COLUMN+CELL
test_table column=l:hbase, timestamp=1519463374193, value=RWXCA
test_table_01 column=l:hbase, timestamp=1519463409831, value=RWXCA
user_01 column=l:hbase, timestamp=1519463393177, value=RWXCA
3 row(s) in 0.1600 seconds遇到问题，在理解整体架构原理的情况下，有目的，有范围的一步步检查，终归是可以解决的。
