我的服务器启动几分钟后崩溃了，我在 /var/log/boot.log 中发现了这一点：
[ OK ] Started LSB: disk temperature monitoring daemon.
[FAILED] Failed to start LSB: Starts and stops the iSCSI software target.
See 'systemctl status iscsitarget.service' for details.
[ OK ] Started LSB: VirtualBox Linux kernel module.
[ OK ] Started OpenVPN connection to server.
Starting Permit User Sessions...
[ OK ] Started Permit User Sessions.
Starting Hold until boot process finishes up...
[ OK ] Started MySQL Community Server.
[ OK ] Started LSB: This service starts and stops VMware services.
Starting LSB: This services starts and stops the Workstation as a Server daemon....
[ OK ] Started LSB: This services starts and stops the Workstation as a Server daemon..
[FAILED] Failed to start vboxadd.service.
See 'systemctl status vboxadd.service' for details.
Starting vboxadd-service.service...
Starting Light Display Manager...
[FAILED] Failed to start vboxadd-service.service.
See 'systemctl status vboxadd-service.service' for details.
在服务器崩溃之前，我可以通过 ssh 访问它，一切看起来都很正常。
我怎么解决这个问题？
我执行以下命令后服务器暂时恢复正常，但不知道为什么。
933 systemctl stop vboxadd.service
934 systemctl disable vboxadd-service.service
935 sudo systemctl stop vboxadd-service.service
936 sudo systemctl disable vboxadd.service
937 sudo apt purge virtualbox*
938 shutdown -r now
939 svn co https://svn.code.sf.net/p/iscsitarget/code/ iscsitarget
940 apt-get update
941 apt-get upgrade
942 apt-get -f install
943 apt-get update
944 apt-get install --reinstall iscsitarget-dkms
945 systemctl enable iscsitarget
946 systemctl restart iscsitarget
947 systemctl status iscsitarget.service
948 journalctl -xe
949 vim /usr/src/aufs-4.9+20161219/dkms.conf
950 apt-get remove -y docker-engine
951 apt-get install -y docker-engine
952 uname -r
953 docker-ce
954 apt-get install -y docker-engine
955 cat /etc/os-release
956 uname -a
957 dpkg --list | grep linux-image
958 dpkg --list | grep linux-headers
959 dpkg --list | grep raspberrypi-
960 apt full-upgrade
961 apt-get update
962 apt full-upgrade
963 sudo apt autoremove
964 apt-get install -f
965 dpkg --configure -a
966 yy
967 y
968 yy
969 y
970 apt-get install -f
971 ls
972 sudo apt autoremove
973 sudo apt -f autoremove
974 apt full-upgrade
975 apt -f full-upgrade
976 sudo apt-get install -f && sudo dpkg --configure -a
977 apt-get update && sudo apt-get -y upgrade && sudo apt-get -y dist-upgrade
978 apt-get update
979 apt-get -y upgrade
980 apt-get -y upgrade -f
981 apt-get -y dist-upgrade
982 apt-get -y dist-upgrade -f