As I read it, in the end they did not lose any data. But it took a lot of effort to not lose data - some had to be recovered from the media in the affected datacenters.RTH10260 wrote: ↑Tue Oct 02, 2018 6:06 pmIt's my understanding that Microsoft did not lose any data. Only their datacenters crashed and required hardware replacements, after which servers would again get loaded with the duplicates from other surviving srevers, ready for a merrygoround with the next storm. The lesson for customers is that even big names cannot garantee permanent availability of services with the cloud concept.
A problem with live systems is that "complete backups" are not sufficient, and "not losing data" is not sufficient. You need to be transactionally consistent with all other systems you've committed to (or who have committed to you), affected or unaffected. You also need to stay transactionally consistent with transactions that you yourself are continuing to do on non-impaired parts of your system. And you need to do this in a way that you can take advantage of distributed processing when things are working as planned.
A part of my work involves enterprise and cloud storage providers. It is truly amazing how many allegedly bright Computer Science folks have no clue on this stuff..