Linuxシステムでのシステム時間とハードウェア時間の表示

Linuxシステムでのシステム時間とハードウェア時間の表示
1.具体的なコマンドは以下のとおりです.

        
[root@littlelawson hbase-1.4.0]# date
Mon Jun 18 10:36:45 PDT 2018

      
[root@littlelawson hbase-1.4.0]# date -s 21:48:00
Mon Jun 18 21:48:00 PDT 2018

        
[root@littlelawson hbase-1.4.0]# hwclock
Mon 18 Jun 2018 09:51:01 PM PDT  -0.969901 seconds

      ，' / /    '
[root@littlelawson hbase-1.4.0]# hwclock --set --date='06/18/18 21:50'

[root@littlelawson hbase-1.4.0]# hwclock --systohc

[root@littlelawson hbase-1.4.0]# hwclock
daMon 18 Jun 2018 09:52:23 PM PDT  -0.391427 seconds

[root@littlelawson hbase-1.4.0]# date
Mon Jun 18 21:52:23 PDT 2018

2.hwclock[hardware clock]コマンドについて

-s, --hctosys
              Set the System Time from the Hardware Clock.#        ，      
              Also set the kernel’s timezone value to the local timezone as
              indicated    by    the   TZ   environment   variable   and/or
              /usr/share/zoneinfo, as tzset(3) would interpret  them.   The
              obsolete  tz_dsttime  field of the kernel’s timezone value is
              set to DST_NONE. (For details on  what  this  field  used  to
              mean, see settimeofday(2).)

              This  is  a  good  option to use in one of the system startup
              scripts.

       -w, --systohc
              Set the Hardware Clock to the current System Time.##        ，