> I think the "high availability by redundancy" story is oversold.
More generally, an awful lot of systems that'd be fine with a SQL mirror (non-failover), some real backups on top, and a restore-from-backup event every 3-5 years, plus the occasional 1hr maintenance window, are instead made "HA" and "redundant" at 10+x the ops cost and, unless very well done, with even more down-time anyway because they're so damn complex.
More generally, an awful lot of systems that'd be fine with a SQL mirror (non-failover), some real backups on top, and a restore-from-backup event every 3-5 years, plus the occasional 1hr maintenance window, are instead made "HA" and "redundant" at 10+x the ops cost and, unless very well done, with even more down-time anyway because they're so damn complex.