请看initramfs文件的以下解析:
1 [root@ant-colonies boot]# ls 2 config-2.6.32-573.el6.x86_64 lost+found 3 efi symvers-2.6.32-573.el6.x86_64.gz 4 grub System.map-2.6.32-573.el6.x86_64 5 initramfs-2.6.32-573.el6.x86_64.img vmlinuz-2.6.32-573.el6.x86_64 6 [root@ant-colonies boot]# file initramfs-2.6.32-573.el6.x86_64.img 7 initramfs-2.6.32-573.el6.x86_64.img: gzip compressed data, from Unix, last modified: Thu Jan 19 21:36:05 2017, max compression 8 [root@ant-colonies boot]# mkdir /initrd 9 [root@ant-colonies boot]# cp initramfs-2.6.32-573.el6.x86_64.img /initrd 10 [root@ant-colonies boot]# cd /initrd 11 [root@ant-colonies initrd]# mv initramfs-2.6.32-573.el6.x86_64.img initramfs-2.6.32-573.el6.x86_64.gz 12 [root@ant-colonies initrd]# gunzip initramfs-2.6.32-573.el6.x86_64.gz 13 [root@ant-colonies initrd]# ls 14 initramfs-2.6.32-573.el6.x86_64 15 [root@ant-colonies initrd]# file initramfs-2.6.32-573.el6.x86_64 16 initramfs-2.6.32-573.el6.x86_64: ASCII cpio archive (SVR4 with no CRC)
由以上图示可以看出:虚拟文件系统模拟的就是根的启动过程
下面通过chroot来模拟一个虚拟的文件系统(虚拟根):