realmd needs an option "--service-principal"

[Alexander Fieroch]

I join our clients to AD by realm and add options to fill the computer account's attributes:

realm join --user=$USER --user-principal=host/$(hostname -s)@DOMAIN --computer-ou="OU=Linux-Clients,OU=Client Computer" --automatic-id-mapping=no --client-software=sssd --membership-software=samba --computer-name=$(hostname -s) --os-name="$(grep NAME /etc/os-release | head -1 | sed 's/NAME="\(.*\)"/\1/g')" --os-version=$(grep VERSION_ID /etc/os-release | sed 's/VERSION_ID="\(.*\)"/\1/g') DOMAIN

What is still missing is to add service-principalnames for the AD computer account attribute "servicePrincipalName".
So it would be great to have an option like "--service-principal=nfs" to set the attribute. Meantime I still have to add it by "setspn -s nfs/HOSTNAME HOSTNAME" on the Windows DC.

Thanks!

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Ubuntu 19.04
realmd 0.16.3-2