Resilient file infrastructure
In the last 2-3 years a number of key services have been advanced, upgraded and replaced. With these changes have come some architectural alterations that have strained our ability to guarantee data integrity in the event of a disaster. This has come about due to design choices by vendors primarily on how they retain objects in their applications. For example in some of the services vendors choose now to retain both transactional database information and real objects that are referred to in the database in associated external file systems. This might take the form of a Word document or a PDF for example where the application holds metadata in the transactional database and the real file in an external file system.
Databases are now typically synchronised in real time across two datacentres at King’s Buildings and Appleton Tower and it follows that it is now very important that the objects held in the external file systems are replicated in a similar manner to ensure that in the event of a disaster both transactional database information and the associated external file system objects can be recovered to the same point in time with no data loss.
Most recently attempts were made to address this problem and within the tel013 and uwp006 projects a resilient file system that could replicate content from King’s Buildings to Appleton Tower was prepared and evaluated. However during evaluation a number of technical constraints emerged that proved that this solution would not be viable.
The requirement for the resilient file system still exists and so we propose to do the following;
• Gather a complete set of the applications and their priority that should make use of this resilient file system service
• Evaluate the technical demands that these applications will impose on a resilient file system and prepare a set of technical requirements
• Catalogue a set of potential solutions that might be used to satisfy these requirements
• Evaluate these potential solutions against the technical requirements
• Identify the preferred solution and prepare a recommendation on which solution to implement
The information gathering and evaluation will be carried out by staff in both ITI and Applications Division
Iain Fiddes