Hbase WALs(HLog) 文件存储，查看

WALs(HLog) 存储

HLog 存储位置是在，hbase配置目录下WALs目录，默认为 /hbase/WALs 与 /hbase/oldWALs

/hbase/WALs : 存储未过期的日志/hbase/oldWALs : 存储已过期的日志

这里先查看WALs日志目录，目录格式为：hostname1 为服务器hostname ， 16020 为hbase 端口，1561747594397 为目录创建时间

drwxr-xr-x   - hbase hbase          0 2019-08-13 15:58 /hbase/WALs/hostname1,16020,1561747594397

目录下存放着Hlog

-rw-r--r--   2 hbase hbase  268440291 2019-08-13 15:58 /hbase/WALs/hostname1,16020,1561747594397/hostname1%2C16020%2C1561747594397.hostname1%2C16020%2C1561747594397.regiongroup-0.1565681614115

查看日志内容

 hbase hlog -j /hbase/WALs/hostname1,16020,1561747594397/hostname1%2C16020%2C1561747594397.hostname1%2C16020%2C1561747594397.regiongroup-0.1565681614115

Hbase 2.0 之后使用

 hbase wal -j /hbase/WALs/hostname1,16020,1561747594397/hostname1%2C16020%2C1561747594397.hostname1%2C16020%2C1561747594397.regiongroup-0.1565681614115

更多介绍参考：https://hbase.apache.org/book.html#wal

Deprecated in 1.0 admin commands have been removed.

The following commands that were deprecated in 1.0 have been removed. Where applicable the replacement command is listed.

The 'hlog' command has been removed. Downstream users should rely on the 'wal' command instead.

看下命令介绍：-j 以json输出，-p输出value值，默认是补输出value

[root@hostname ~]# hbase wal 
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release
usage: WAL <filename...> [-h] [-j] [-p] [-r <arg>] [-s <arg>] [-w <arg>]-h,--help             Output help message-j,--json             Output JSON-p,--printvals        Print values-r,--region <arg>     Region to filter by. Pass encoded region name; e.g.'9192caead6a5a20acb4454ffbc79fa14'-s,--sequence <arg>   Sequence to filter by. Pass sequence number.-w,--row <arg>        Row to filter by. Pass row name.

Hlog查看

hbase wal /hbase/WALs/hostname1,16020,1561747594397/hostname1%2C16020%2C1561747594397.hostname1%2C16020%2C1561747594397.regiongroup-0.1565681614115  | less 
row=d687aa8919594289543efde17047217b, column=fn:friends_count
row=d687aa8919594289543efde17047217b, column=fn:created_at
row=d687aa8919594289543efde17047217b, column=fn:description
row=d687aa8919594289543efde17047217b, column=fn:experience
row=d687aa8919594289543efde17047217b, column=fn:uid
row=d687aa8919594289543efde17047217b, column=fn:province
row=d687aa8919594289543efde17047217b, column=fn:zan_count
row=d687aa8919594289543efde17047217b, column=fn:verified_reason
row=d687aa8919594289543efde17047217b, column=fn:level_info
row=d687aa8919594289543efde17047217b, column=fn:reposts_count
row=d687aa8919594289543efde17047217b, column=fn:isRepeat
row=d687aa8919594289543efde17047217b, column=fn:profileImageUrl
row=d687aa8919594289543efde17047217b, column=fn:read_count
row=d687aa8919594289543efde17047217b, column=fn:growthSpeed
row=d687aa8919594289543efde17047217b, column=fn:verified
row=d687aa8919594289543efde17047217b, column=fn:verified_type
row=d687aa8919594289543efde17047217b, column=fn:growthValue
row=d687aa8919594289543efde17047217b, column=fn:url

Hlog过期

当数据从memstore写入到磁盘中，Hlog就已经没有用了，会把/hbase/WALs目录下的数据移动到/hbase/oldWALs 目录下，oldWALs目录下的数据会根据 hbase.master.cleaner.interval (默认1分钟)配置的时间定期去检查，如发现有数据会清除，清除前还会检验一个参数 hbase.master.logcleaner.ttl ，也就是说数据保存1分钟以上才会删除，如果一分钟内数据直接从memstore写入到了磁盘，oldWALs下的数据也不会被删除