How to clear User Logon records and command history in Linux

[Root @ localhost root] # echo>/var/log/wtmp # garbled characters are cleared when the file is opened by default, ip address and other information can be found [root @ localhost root] # last # user logon information cannot be found at this time to clear records of system logon failures [root @ localhost root] # echo>/var/log /btmp # garbled characters when this file is opened by default, you can find the logon Failure Information [root @ localhost root] # lastb # the logon failure information cannot be found. Clear the historical execution command [root @ localhost root] # history-c or, clear the file in the user directory to [root @ localhost root] # echo>. /. bash_history 1.vi/root/history # create a record file. history-c # clear record 3. history-r/root/history.txt # import record 4. history # query the import result www.2cto.com example [root @ localhost root] # vi/root/history [root @ localhost root] # history-c [root @ localhost root] # history-r/ root/history.txt [root @ localhost root] # history 1 echo>/var/log/wtmp 2 last3 echo>/var/log/btmp4 lastb 5 history-c 6 echo>. /. bash_history7 history author akingde