I want to see an article about making use of not-perfectly-up-to-date backups databases in a different region. Why can't reddit dump a copy of their new articles and comments to the west coast every night, then if the east coast dies, fire that up? Sure it's missing a chunk of the latest day's data, but that has to beat either completely being down or jumping through the technical hoops required to keep separate regions in sync across the internet. Then collect new articles and comments on the backup for a while, and when east coast is fixed merge the new data back over to east coast and go back about business?
Ditto for any web 2.0 we-are-a-fancy-shared-commenting-blog service, or anything that is fundamentally time based aggregation of information. Do database replication systems just not handle the concept of working with temporary gaps in the data?
A lot of AWS stuff can't be transferred between regions. There's no way to move an EBS snapshot from east to west coast except to copy the thing across the public internet. Once it's over there on the west coast, to "fire that up" they have to launch app servers, database servers, cache servers, etc. whose configurations they had to keep mirrored from their normal region. They need to get all those backups onto EBS disks without using the same snapshot features they probably automated in their main region, attach them to the right instances... For a team with a single sysadmin, it's not as simple as you make it sound.
Ditto for any web 2.0 we-are-a-fancy-shared-commenting-blog service, or anything that is fundamentally time based aggregation of information. Do database replication systems just not handle the concept of working with temporary gaps in the data?