Home > Storage > PowerScale (Isilon) > Product Documentation > Management and Migration > PowerScale OneFS User Mapping: Mapping Identities Across Authentication Providers > Avoid common UIDs and GIDs
In addition, you should not use well-known UIDs and GIDs in your ID ranges because they are reserved for system accounts. UIDs and GIDs below 1000 are reserved for system accounts; do not assign them to users or groups.