ubuntu 清理boot目录

1.uname -r

4.4.0-121-generic

2.dpkg --get-selections|grep linux

console-setup-linux install
libselinux1:amd64 install
linux-base install
linux-firmware install
linux-generic install
linux-headers-4.4.0-104 purge
linux-headers-4.4.0-108 install
linux-headers-4.4.0-108-generic install
linux-headers-4.4.0-109 install
linux-headers-4.4.0-109-generic install
linux-headers-4.4.0-112 install
linux-headers-4.4.0-112-generic install
linux-headers-4.4.0-116 install
linux-headers-4.4.0-116-generic install
linux-headers-4.4.0-119 install
linux-headers-4.4.0-119-generic install
linux-headers-4.4.0-121 install
linux-headers-4.4.0-121-generic install
linux-headers-4.4.0-124 install
linux-headers-4.4.0-124-generic install
linux-headers-4.4.0-127 install
linux-headers-4.4.0-127-generic install
linux-headers-4.4.0-128 install
linux-headers-4.4.0-128-generic install
linux-headers-4.4.0-130 install
linux-headers-4.4.0-130-generic install
linux-headers-4.4.0-87 install
linux-headers-4.4.0-87-generic install
linux-headers-generic install
linux-image-4.4.0-116-generic install
linux-image-4.4.0-119-generic install
linux-image-4.4.0-121-generic install
linux-image-4.4.0-124-generic install
linux-image-4.4.0-127-generic install
linux-image-4.4.0-128-generic install
linux-image-extra-4.4.0-116-generic install
linux-image-extra-4.4.0-119-generic install
linux-image-extra-4.4.0-121-generic install
linux-image-extra-4.4.0-124-generic install
linux-image-extra-4.4.0-127-generic install
linux-image-extra-4.4.0-128-generic install
linux-image-extra-4.4.0-130-generic install
linux-image-extra-virtual install
linux-image-generic install
util-linux install

3.后边带版本号的是可以卸载的内核，与uname -r 结果对比，删除其他的版本的内核

4.删除之前/boot 目录必须有空间，如果空间为0，删除的命令不能执行，可以先移走一个文件，然后做软连接，清理其他的文件之后，还原回来，如果移走文件空间没有释放，需要重启服务器

5.sudo dpkg --purge [内核名称]

6.linux-image-extra 先删除，这个是依赖linux-image的

7.保留距离当前版本最近一个版本的内核