Before you have a Linux terminal - the zipl boot menu
Do not confuse the zipl boot menu with a Linux® terminal.
Depending on your setup, a zipl boot menu might be displayed when you perform an IPL. The zipl boot menu is part of the boot loader that loads the Linux kernel and is displayed before a Linux terminal is set up. The zipl boot menu is very limited in its functions. For example, there is no way to specify uppercase letters because all input is converted to lowercase characters.