I had some fun with OEM adding cman targets.
At least for me it wasn't as documented as I'd would have preferred.
(so it's more a note-to-self than anything of public interest)

https://berxblog.blogspot.com/2022/12/oem-135-add-cman-target.html
https://berxblog.blogspot.com/2022/12/oem-135-add-cman-target-with-emcli.html