When you join a vCenter Server system to a linked mode group, the roles defined on each vCenter Server system in the group are replicated to the other systems in the group.
If the roles defined on each vCenter Server system are different, the roles lists of the systems are combined into a single common list. For example, if vCenter Server 1 has a role named Role A and vCenter Server 2 has a role named Role B, then both servers will have both Role A and Role B after they are joined in a linked mode group.
If two vCenter Server systems have roles with the same name, the roles are combined into a single role if they contain the same privileges on each vCenter Server system. If two vCenter Server systems have roles with the same name that contain different privileges, this conflict must be resolved by renaming at least one of the roles. You can choose to resolve the conflicting roles either automatically or manually.
If you choose to reconcile the roles automatically, the role on the joining system is renamed to vcenter_namerole_name where vcenter_name is the name of the vCenter Server system that is joining the Linked Mode group and role_name is the name of the original role.
If you choose to reconcile the roles manually, connect to one of the vCenter Server systems with the vSphere Web Client and rename one instance of the role before proceeding to join the vCenter Server system to the Linked Mode group.
If you remove a vCenter Server system from a linked mode group, the vCenter Server system retains all the roles it had as part of the group.