US Patent 8131784 Multiple node quota filter

An apparatus and a method that allow a quota to be implemented over a data storage system having data associated with the user stored in multiple volumes or directories across multiple storage servers. The quota limits a user or a group of users to a defined amount (e.g., quota) of storage resources of the storage system. The method may include monitoring input-output (IO) data access requests on each of the multiple storage servers, for example, using a pluggable quota filter on each of the storage servers, determining a total usage of storage resources for a particular user over the multiple storage servers, and limiting the user to the quota over the multiple storage servers.