4.2. Downloading Files from Debian Mirrors

To find the nearest (and thus probably the fastest) mirror, see the list of Debian mirrors.

When downloading files from a Debian mirror, be sure to download the files in binary mode, not text or automatic mode. It's important to replicate the directory structure you find on the mirror to create a local `sub-mirror'. You should start your local directory structure at the level under installer-s390, for example:

current/images/subarchitecture/netboot/initrd.gz

You don't need to download every file under that level, just those that apply to you (you'll find out which ones apply as you read on). Just name the directories the same as the mirror's, and keep the files in their proper directories.

If your machine is set up to automatically decompress/decode files you download, you must turn that feature off when downloading the installation system files. They will be decompressed just-in-time by the installer. Decompressing in your current system will waste space and time, and if the original compressed archives are deleted by the decompression program, they won't be there later when the installer needs them.

4.2.1. Installation Options

Files you may need fall into three categories:

  1. Files needed to boot into the installation system (for example, kernel.debian, parmfile.debian, and initrd.debian)

  2. Files the installation system will need access to after it has been booted in order to install the operating system kernel and peripheral drivers (for example, net-drivers.img and cd-drivers.img)

  3. Base system installation files

If you have a working Ethernet connection on the computer, and your Ethernet card is of one of the types compiled into the installation kernel, you may only need the install system boot files. The installer is capable of installing drivers and the rest of the system over the network for many common Ethernet cards.

If you have an Ethernet connection for which the installer doesn't have built-in support, you may need both the install system boot files and the peripheral driver installation files.

If you are installing on a system without a working network connection, or if your network connection is via PPP (using a modem) rather than Ethernet, you will need to obtain all three types of files before starting the installation. The base system installation files are available on the first Debian CD (or on its smaller variant called netinst, which is under 120MB). You can use this ISO image even if you don't have a CD-ROM drive.

If you're not sure which files you need, just start with the install system boot files. If your first attempt to configure the network within the installer fails, you can just quit, get the extra files you need, and re-start the installation.

4.2.2. Choosing the Right Installation Set

Installation files include kernel images, which are available for various subarchitectures. Each subarchitecture supports a different set of hardware. The kernel config files for these subarchitectures can be found in their respective directories in a file named kernel-config. The subarchitectures available for S/390 are:

`tape'

Includes a kernel image which supports booting (IPL) from a tape (emulated or real) and a DASD (Direct Access Storage Device). You need these files if you want to install Debian GNU/Linux native or in an LPAR (logical partition) but they can also be used to install under VM with a tape (real or emulated).

`vmrdr'

Includes a kernel image which supports booting (IPL) from the VM reader and a DASD, These files can only be used if you want to install Debian GNU/Linux in a VM guest.

Both of these kernels include almost all drivers supported by Linux built as modules. Support for standard hardware is compiled into the kernel, so it is unlikely that you will need to configure any modules during installation.

Both kernels were also built to directly support IBM's OCO modules. You can simply download then from IBM's developerWorks web site and load them into the running kernel. Please make sure that you pick the modules for the standard kernel, i.e. not the ones for a kernel with the ``on-demand'' timer patch.

The kernel config files for these subarchitectures can be found in their respective directories in a file named kernel-config.

4.2.3. Where to Find Installation Files

The boot image contains a compressed Linux boot kernel. It is used for the Linux kernel when the kernel is being installed on your machine. The kernel binary vmlinuz is an uncompressed binary kernel. It is used when booting the installer from tape, emulated tape or the VM reader.

The root floppy image root.img contains a compressed RAMdisk filesystem which gets loaded into memory after you boot the installer.

The peripheral drivers may be downloaded as a series of floppy images or as a tarball (drivers.tgz). The installer system will need access to the drivers file during installation. If you have a hard drive partition or connected computer which will be accessible to the installer (see below), the tarball will be more convenient to handle. The floppy image files are needed only if you must install the drivers from floppies.

When downloading files, you should also pay attention to the type of file system you are downloading them to, unless you will use floppies for the kernel and drivers. The installer can read files from many kinds of file systems, including FAT, HFS, ext2fs, and Minix. When downloading files to a *nix file system, choose the largest possible files from the archive.

During the installation, you will erase the partition(s) on which you are installing Debian before beginning the installation. All downloaded files must be placed on partitions other than those on which you are planning to install the system.