虚拟机安装SSH时报错：
hub@hub-virtual-machine:~$ sudo apt-get install openssh-server E: Could not get lock /var/lib/dpkg/lock - open (11: Resource temporarily unavailable) E: Unable to lock the administration directory (/var/lib/dpkg/), is another process using it?
此时，进行以下操作：清除lock-fronted和lock
hub@hub-virtual-machine:~$ sudo rm /var/lib/dpkg/lock-frontend hub@hub-virtual-machine:~$ sudo rm /var/lib/dpkg/lock
尝试重新安装，发现还是报错，
hub@hub-virtual-machine:~$ sudo apt-get install openssh-server E: Could not get lock /var/lib/dpkg/lock-frontend - open (11: Resource temporarily unavailable) E: Unable to acquire the dpkg frontend lock (/var/lib/dpkg/lock-frontend), is another process using it?
解决办法：进入 /var/lib/dpkg/，重新安装成功
