[xxxx@xxxx~]$ ls -a
bash: ls: command not found…
Similar command is: ‘lz’
[xxxx@xxxx~]$ ll -a
bash: ls: command not found…
Similar command is: ‘lz’
[xxxx@xxxx~]$ ls -a ~/
bash: ls: command not found…
Similar command is: ‘lz’
[xxxx@xxxx~]$
解決辦法：
執行：
export PATH=/bin:/usr/bin:$PATH