The phyglos-bootloader bundle

Functionality

The phyglos-bootloader bundle is used to install a bootloader for the TARGET system. Not all the TARGET systems may need a bootloader, e.g. the final system may boot first into another Linux distribution or operating system and the bootloader there installed is capable of chaining to the TARGET partition. However, if the TARGET system is installed in a new disk and expected to be used as the primary (or the only) disk to boot in the TARGET system, then a bootloader is needed.

This bundle installs a bootloader in a disk and configures the bootloader to find the proper root disk and root partition where to load, at boot time, the ‘phySystem’ kernel from.

Configuration

Bundle variables

BUNDLE_SOURCES: This bundle uses the common phyglos group of source packages.

BUNDLE_KEEP_LA: This bundle does not need to keep the .la files. The value of this variable is inherited from bandit.conf unless specifically set in this file.

Boot disk

PHY_BOOT_DISK: The device for the boot disk, where the bootloader is to be installed. Use the command lsblk to check the correct value. This device name is set to a value as seen at installation time from the BUILDER system. It may differ from the final value that will be seen by the bootloader at boot time.

Root disk

PHY_BOOT_ROOT_DISK: The name for the root disk and partition where the bootloader will seek the root partition. Set this variable to a value as will be seen at boot time. It may differ from the value seen by the BUILDER system at installation time. Use the bootloader conventions for the names, e.g. “(hd0,1)”

PHY_BOOT_ROOT_TYPE: The partition type for the root partition. Use the bootloader conventions for partition types, e.g. in GRUB both ext3 and ext4 partition types are set to “ext2” value.

PHY_BOOT_ROOT_PART: The final boot partition where the bootloader will search for the kernel.

Kernel to boot

By default, the phyglos-bootloader will source the configuration from the phyglos-kernel bundle to set the kernel to boot from. If other values are needed, they can be explicitly set. All these values are used to search for a file containing the kernel image named: vmlinuz-${PHY_KERNEL_VER}-${PHY_KERNEL_ARCH}-${PHY_KERNEL_HW}

PHY_KERNEL_VER: The kernel version to search for, e.g. “4.14”

PHY_KERNEL_ARCH: The kernel processor architecture, e.g. “x86_64”

PHY_KERNEL_HW: The kernel variant, e.g: “pc_generic”

Kernel boot configuration

PHY_BOOT_LINUX_CMDLINE: This variable can be used to specify additional parameters to pass to the Linux kernel at boot time.