Flextech, the content division of Telewest, is the provider of the largest number of basic thematic channels in the UK. Its core business is to provide entertainment, information and interactive content and services to the multi-channel television and on-line markets.

They rely on a computing infrastructure not only to produce channels and programme content but also to transfer this content to air. In common with almost all of the broadcast industry, much of the day to day operation is computer controlled and highly automated.

Project Requirements
Flextech needed to produce an electronic programme guide service to feed TV listing information to Sky, Telewest, NTL and others, that could support all of its television channels and their programme content. This was designed to run on a Sun E450 and an Oracle Database. To save on costs it was determined that developing a pair of systems to fail over, and to not be entirely fault tolerant would be more cost effective than trying to produce a fully resilient 24x7 operation.

The Solution
Layer3 was asked to work with the database designers to implement the fail-over solution. Developing a series of small programs that could ensure that the core feeds to the system were on both the primary and secondary machines was the key to the solution. Each evening the database was backed up to tape as well as being copied to the secondary server. This was made possible by using Veritas Volume Manager provide the virtual disk management, splitting out a mirror as a snapshot and then resyncing after the backup. 

Benefits
• Greatly simplified programming as database designers did not need to understand resilience issues - £300,000 estimated saving.
• Developed and implemented after the initial system started operation
• Large cost saving in both development and operation - £90,000 cost
• Recovery within the hour, secondary system was remotely located to increase site resilience and as part of disaster recovery
• Disaster recovery cost saving as system located at a partner companies premises - £100,000 site costs
• Technology transferable to majority of databases
• Manual or completely automatic recovery switch