Originally Posted by
teCh0010
SABRE is one of the biggest mainframe shops in TX...
Facebook and Twitter can architect their applications in different ways because their business demands are different. Facebook is fine with you not seeing your buddies update for a few minutes because global DNS load balancing sent you different DC and their change hasn't replicated there. Eventual consistency is fine.
Some business requirements are aligned with cloud native application design, and some aren't.
Banking and airline applications are sequential transactions that require immediate consistency. Immediate consistency requires a single source of truth at the data persistence layer. One DB that you read and write from. Milliseconds matter. If you used the type of data persistence layers that lead to cloud native applications that can survive an entire DC going down you aren't recording sequential transactions. There is a single ticket in K bucket, I can't sell it to two people because they connected to different datacenters. There is one seat 16a, I can't assign it to two people because they connected to different data centers.
You can replicate the data persistence layer, but it is going to take time to fail over. I'm sure DL replicates the SAN under their mainframes and X86 servers, but it takes time to fail over. You have to make the decision to failover or wait it out based on how long you thing the outage will take.
I'd agree with many of your statements except that there are 1000's of busineses today that are performing the same logic on vastly superior systems. The idea of single state is NOT new or even airline centric. You're got to be kidding yourself if you think the airline industry is THAT unique. This isn't new or ground braking.
Want an example in the airline industry? How do GDS's some distribute inventory and fare invormation with any (that I know of) interruption in many many years?
Distriubuted mainframes. It's possible. Let's stop this idea of delta is smarter than IT. they aren't. It's proven. They need better people (no more dissimilar than IT organization when this happens).