Data storage apparatus that either certifies a recording medium in the background or verifies data written in the recording medium

An information processing system, comprising:

• a host computer;
• a recording medium;
• and
• a data storage apparatus connected to said host computer, capable of certifying said recording medium set therein in background by writing dummy data in said recording medium and verifying said dummy data, stores data provided from said host computer, receives a request from said host computer to write said data in a designated region of said recording medium, writes said data in said designated region, determines whether said designated region has been certified, verifies, if said designated region has not been certified in the background, said data written in said designated region by comparing with the buffered data, and writes, if a portion of said designated region is found to be defective, a portion of the buffered data corresponding to data written in the defective portion of said designated region, in a predetermined alterative region of said recording medium.

A method of writing data provided from an exterior, in a recording medium, comprising:

• a step of receiving a request from said exterior to write said data in a designated region of said recording medium;
• a step of writing said data in said designated region;
• a step of determining whether said designated region has been certified;
• a step of verifying, if said designated region has not been certified, said data written in said designated region;
• and
• a step of writing, if a portion of said designated region is found to be defective, a portion of said data corresponding to data written in the defective portion of said designated region, in a predetermined region of said recording medium.