Although Knowledge Base URLs from the legacy system will redirect properly for the next year to the Knowledge Base in ServiceNow, full redirect mappings are available in a shared KB URL redirect mappings folder which you can reference if you need to update websites or other resources.
If a legacy URL has no redirect, that particular article was archived sometime before the transition. Archived articles are no longer available in the new KB, but the Knowledge Management (KM) team can access them if needed.
If you have questions or comments, contact the KM team at kb@iu.edu.