In order to run the installation system on s390x a working network setup is needed and a ssh session is recommended.

The booting process starts with a network setup that prompts you for several network parameters. If the initial setup is successful, you will usually login to the system by starting an ssh session which will launch the standard installation system (alternatively you can proceed using the console - however, this is less comfortable).

On s390x you can append boot parameters in the parm file. This file can either be in ASCII or EBCDIC format. It needs to be fixed-width with 80 characters per line. A sample parm file parmfile.ubuntu is provided with the installation images, located in the ./boot folder. If a parameter is too long to fit into the 80 characters limit it can simply be continued in the first column of the next line. All the lines are concatenated without spaces when being passed to the kernel. In total 11 lines (plus additonal 10 characters in the 12th line) can be used.

If you boot the installer in a logical partition (LPAR) or virtual machine (z/VM) where a lot of devices are visible, you can instruct the kernel to restrict the list to a fixed set of devices. This is advised for the installer's boot process if a lot of disks are visible, most likely in LPAR mode. The “cio_ignore” option supports both a blacklist (to only disallow a few devices) and a whitelist (to only allow specific devices):

 # blacklist: just ignore the two devices 300 and 301
 cio_ignore=0.0.0300-0.0.0301
 # whitelist: ignore everything but 1150, FD00, FD01 and FD02
 cio_ignore=all,!0.0.1150,!0.0.fd00-0.0.fd02

Please note that all devices numbers' hex digits need to be specified in lower case. Furthermore if this boot parameter is used all devices need to be listed: this includes at least disks, network devices and the console. To be considered during the installer's boot process the above option needs to be added to parmfile.ubuntu.