Former network engineer here, can confirm. Time and again I've seen redundant systems create their own problems where without all that extra complexity things would have been fine.
Even ISPs and CDNs I worked with sometimes have surprisingly uncomplicated redundancy systems (sometimes just a handful of small routers they are very much ready to power down to cut over to backup paths or bring up new paths) and often they do not use the more complicated methods.
The catch with complicated redundancy is there is always a very close relationship or protocol or something between redundant components, bet it storage systems, network systems, anything. Inevitably a system goes down or loses its mind and takes it's redundant peers with it.... every new system you introduce is one more piece that could reach out and take everyone else with it. I saw it time and again, and again...
Even ISPs and CDNs I worked with sometimes have surprisingly uncomplicated redundancy systems (sometimes just a handful of small routers they are very much ready to power down to cut over to backup paths or bring up new paths) and often they do not use the more complicated methods.
The catch with complicated redundancy is there is always a very close relationship or protocol or something between redundant components, bet it storage systems, network systems, anything. Inevitably a system goes down or loses its mind and takes it's redundant peers with it.... every new system you introduce is one more piece that could reach out and take everyone else with it. I saw it time and again, and again...