5 Description of pre-built images #

SLE Micro can be deployed using pre-built images. Currently, there are two types of images available: raw disk images and selfinstall ISOs.

SLE Micro raw images are delivered for the AMD64/Intel 64 architecture, IBM Z ZSeries and also AArch64. The selfinstall images are currently delivered only for the AMD64/Intel 64 architecture. The pre-built images are intended to be configured on the first boot by using either Ignition or Combustion. The boot loader detects the first boot; for more information see Section 5.1, “First boot detection”. Each image has default mounted subvolumes as described in Section 7.1, “Default partitioning”. The procedure of deploying these images is described in Chapter 8, Deploying the raw image.

On the pre-built images, firewall is disabled by default, as running it along with Podman may result in missing Podman-related firewall rules after reloading the firewalld service. Therefore, it is recommended to keep the firewall disabled if you intend to use Podman.

Note: SLE Micro as a VM Host Server

SLE Micro can run as a KVM host server—Xen is not supported. However, there are several limitations of SLE Micro running as a VM Host Server; for details refer to virtualization limits and support.

5.1 First boot detection #

  

The configuration runs on the first boot only. To distinguish between the first and subsequent boots, the flag file /boot/writable/firstboot_happened is created after the first boot took place. If the file is not present in the file system, the attribute ignition.firstboot is passed to the kernel command line, and thus both Ignition and Combustion are triggered to run (in the initramfs). After completing the first boot, the /boot/writable/firstboot_happened flag file is created.

Note: The flag file is always created

Even though the configuration may not be successful, due to improper or missing configuration files, the /boot/writable/firstboot_happened flag file is created.

You may force the first boot configuration on subsequent boot by passing the ignition.firstboot attribute to the kernel command line or by deleting the /boot/writable/firstboot_happened flag file.