Comment 7 for bug 1975922

It can be deploy as rhel customer images with below adjustments:
curtin/curtin$ sudo vi distro.py
DISTRO_NAMES = ['arch', 'centos', 'debian', 'fedora', 'freebsd', 'gentoo',
                'opensuse', 'redhat', 'rhel', 'sles', 'suse', 'ubuntu', 'openEuler']
...

OS_FAMILIES = {
    DISTROS.debian: [DISTROS.debian, DISTROS.ubuntu],
    DISTROS.redhat: [DISTROS.centos, DISTROS.fedora, DISTROS.redhat,
                     DISTROS.rhel, DISTROS.openEuler],

Let euler of to be detected as rhel8 (rpm -E "%rhel")
[root@vm1-openeuler ~]# echo "%rhel 8" >> /etc/rpm/macros.dist
[root@vm1-openeuler ~]# rpm -E "%rhel"
8
[root@vm1-openeuler ~]#

$ maas root boot-resources create name=rhel/8 title="OpenEuler 2003" architecture=amd64/generic content@=openeuler.tar.gz #base ubuntu is still ubuntu; but curtin configure are difference;

Deploy as "Redhat Enterprise Linux" -> "OpenEuler 2003"