linux怎么查看操作系统是bios启动方式还是uefi启动方式？

环境

Red Hat Enterprise Linux 6

Red Hat Enterprise Linux 7

问题

How to identify if the system is installed with UEFI or with Legacy only Boot?

决议

Run the command below to find out if the system is BIOS boot or UEFI boot.

#[ -d /sys/firmware/efi ] && echo UEFI || echo BIOS

For BIOS Boot, it will show as follows.

#[ -d /sys/firmware/efi ] && echo UEFI || echo BIOS

BIOS

For UEFI boot, it will show

#[ -d /sys/firmware/efi ] && echo UEFI || echo BIOS

UEFI