SCCM across untrusted forests

[gr4z]

Hi

I am trying to setup two SCCM sites across untrusted forests:

 

DomainA with SCCM1 (Parent)

DomainB with SCCM2 (Child)

 

I know about the manual key exchanges but all documentation states you must add the computer account SCCM1 into the SMS_SitetoSiteConnection group on SCCM2 and vice versa.

 

But without a trust in place, how do you do it? You cannot navigate to DomainA from within DomainB as it doesn't know anything about it.

 

Thanks for any help.

Graham