Hello there,
The errors you get are caused by failing datacollections. If for instance an enclosure discovers ILOs, switches, it creates a link between these objects if the datacollection finds the extra objects they will be added, in time when datacollection fails the association will break as it has been a while that it could check the info needed for the association.
So the wise thing would be to check the bi weekly datacollection log under the job, this job normaly runs every 2 weeks.