Handbook:Alpha/Blocks/Bootloader

Making a choice
Now that the kernel is configured and compiled and the necessary system configuration files are filled in correctly, it is time to install a program that will fire up the kernel when the system is started. Such a program is called a bootloader.

Several bootloaders exist for Linux/Alpha. Choose one of the supported bootloaders, not all. We document aBoot and MILO.

Default: Using aBoot
First install aboot on the system

The next step is to make the bootdisk bootable. This will start aboot when booting the system. We make our bootdisk bootable by writing the aboot bootloader to the start of the disk.

Although aboot is now installed, we still need to write a configuration file for it. aboot only requires one line for each configuration, so we can do this:

If, while building the Linux kernel, an initramfs was build as well to boot from, then it is necessary to change the configuration by referring to this initramfs file and telling the initramfs where the real root device is at:

Additionally, it is possible to make Gentoo boot automatically by setting up some SRM variables. Try setting these variables from Linux, but it may be easier to do so from the SRM console itself.

Of course substitute dkc100 with whatever the boot device is.

To get in the SRM console again in the future (to recover the Gentoo install, play with some variables, or whatever), just hit to abort the automatic loading process.

When installing using a serial console, don't forget to include the serial console boot flag in aboot.conf. See for some further information.

Aboot is now configured and ready to use. Continue with Rebooting the system.

Alternative: Using MILO
Before continuing, decide on how to use MILO. In this section, we will assume that a MILO boot floppy will be created. When booting from an MS-DOS partition on the hard disk, change the commands appropriately.

To install MILO, we use emerge.

After MILO has been installed, the MILO images should be in. The commands below make a bootfloppy for use with MILO. Remember to use the image for the right Alpha-system.

If the Alpha system is a Ruffian:

Finally, finish off with:

The MILO boot floppy is now ready to boot Gentoo Linux. It may be necessary to set environment variables in the ARCS Firmware to get MILO to start; this is all explained in the MILO-HOWTO with some examples on common systems, and examples of the commands to use in interactive mode.

Not reading the MILO-HOWTO is a bad idea.

Now continue with Rebooting the system.