Lee - gave you an upvote for a great post.
Not losing any data ever and being able to roll back to any in time in the last 15 years gets expensive, particular in large enterprises where the volumes of data are huge. Need proper policies and architectuure. Lets look at an example:
A client I worked for had a requirement to retain all data relating to pension investments for the life of the policy (could be history going back 50 years plus by the time the the investments have matured and been paid out). They had the following data protection regime in place:
- Dual data centres with synchronous replication (protects against DC Disaster).
- in each data centre resilient Oracle database architecture storing to a high availability SAN
- infrastructure was virtualised so inherited the resilience/recovery characteristics of the virtual environment
- Weekly full plus daily incremental backups storing to HP StoreOnce disk based backup storage, replicated to the other data centre
- Weekly full backups offloaded to offsite tape storage on a six week rotation
- Monthly full backups offloaded to offsite tape storage on a 13 month rotation
- Annual full backups offloaded to offsite tape storage on a 15 year rotation
How many copies of the data were they storing? How much did that cost? OK so they had some good Dedup but it wasn't saving them more than about 50% capacity on that expensive HP Storeonce backup infraastructure.
And what really did my head in is they had everything available on production. There was no proper archiving of old data. You couuld lose nearly all the tape without deprecating the data protection architecture very much. The applications manager who had been there 20 years remember a single instance of recalling a tape and the data the business thought they wanted off it was useless to them anyway. It was already on their live system.
Working with the business and architecture we did some really good work to understand the business requirement properly, get a well thought through policy in place, and shaved probably a quarter of a million off thheir backup costs.