Domain Services for Windows (DSfW)Open Enterprise Server 2018 (OES 2018) Linux Service Pack 1
Existing OES2015 or OES2018 Domain Services for Windows configuration has an incoming and/or outgoing trust relationship with a native Active Directory Domain. After being upgraded to OES2018 SP1, one or both of these relationships is broken and users in one domain cannot log in or access resources in the other domain.
This is fixed in OES2018 SP1 Update 7 and OES2018 SP2.
As a workaround, deleting and recreating the trust may fix the problem.
Note that Trust Validation from Active Directory's point of view may fail with Error Code -1073741790 (0xc0000022). If cross-domain validation otherwise works this may be cosmetic as trusts with DSfW are not validated from the AD side.