win10 U盘启动安装 ubuntu 遇到的问题和解决方式

按百度的方法遇到了部分问题，主要有：

1.无法进入U盘启动，

解决：关机重启，按F2进入BIOS（联想笔记本），切换启动模式UEFI 变为Legacy support，F10保存修改，进入系统，再次重启，按F12选USB HDD，可以进入安装过程

2.Ubuntu安装过程中，提示：

The partition table format in use on your disks normally requires to you create a separate partition for boot loader code.
This partition should be marked for use as a "Reserved BIOS boot area" and should be at least 1MB in size.
Note that this is not the same as a partition mounted on /boot.
If you do not go back to the partitioning menu and correct this error, boot loader installation may fail later,
although it may still be possible to install the boot loader to a partition.

解决：分出至少1M给BIOS分区reserved BIOS boot area

3.重新启动无法进入Ubuntu， 使用esayBCD方式也无效

暂无方便的解决方式，只能开机时想进入Ubuntu就F2进BIOS改启动顺序为legacy first ，想进入window就改为uefi。