Local disk-based storage

Local disk storage is the most basic and common form of storage. The operating system and overlaying software manage files and file locations on physical disks. The only level of abstraction available at this level is that the disk storage may be presented to the operating system as a single disk even though there may be several disks, e.g. in a RAID configuration. RAID is capable of providing some resilience if monitored closely for failures, but should always be backed up on to tape as most disk-based solutions are located in a single building and room and are thus vulnerable to natural disasters such as fire. Disk storage in general suffers from lack of expandability, especially when the repository will only store objects in a single location on disk and cannot add multiple locations later.

Pros

• Cheap
• Available off-the-shelf
• Some resilience is provided by RAID-based systems
• Easy to backup and restore

Cons

• Limited to the storage mechanisms and structures applied by the software and operating system, which can often be difficult to understand
• Limited access to data other than through the interfaces provided by the software
• Hard to expand without buying a new solution
• Limited dynamic resilience and susceptible to natural disasters if based in a single location