added to a database stored in memory to allow other certificates to be used, but they must still have a connection to the private portion of the platform key. Secure Boot can also be placed in "Custom" mode, where additional public keys can be added to the system that do not match the private key. Secure Boot is supported by Windows 8 and 8.1, Windows Server 2012 and 2012 R2, Windows 10, Windows Server 2016, 2019, and 2022, and Windows 11, VMware vSphere 6.5 and a number of Linux distributions including Fedora (since version 18), openSUSE (since version 12.3), RHEL (since version 7), CentOS (since version 7), Debian (since version 10), and Ubuntu (since version 12.04.2). , FreeBSD support is in a planning stage. UEFI shell UEFI provides a shell environment, which can be used to execute other UEFI applications, including UEFI boot loaders. Apart from that, commands available in the UEFI shell can be used for obtaining various other information about the system or the firmware, including getting the memory map (memmap), modifying boot manager variables (bcfg), running partitioning programs (diskpart), loading UEFI drivers, and editing text files (edit). Source code for a UEFI shell can be downloaded from the Intel's TianoCore UDK/EDK2 project. A pre-built ShellBinPkg is also available. Shell v2 works best in UEFI 2.3+ systems and is recommended over Shell v1 in those systems. Shell v1 should work in all UEFI systems. Methods used for launching UEFI shell depend on the manufacturer and model of the system motherboard. Some of them already provide a direct option in firmware setup for launching, e.g. compiled x86-64 version of the shell needs to be made available as <EFI_SYSTEM_PARTITION>/SHELLX64.EFI. Some other systems have an already embedded UEFI shell which can be launched by appropriate key press combinations. For other systems, the solution is either creating an appropriate USB flash drive or adding manually (bcfg) a boot option associated with the compiled version of shell. Commands The following is a list of commands supported by the EFI shell. alias attrib bcfg cd cls comp cp date dblk dh dmpstore echo Edd30 EddDebug edit err guid help load ls map mem memmap mkdir mm mode mount pause pci reset rm set stall time type unload ver vol Extensions Extensions to UEFI can be loaded from virtually any non-volatile storage device attached to the computer. For example, an original equipment manufacturer (OEM) can