A lot of the seminal research papers are surprisingly readable! I really recommend reading them to get a good feel for the sort of problems you face at scale and good ways of handling them.
Off the top of my head: a lot of stuff from Google (Dapper, Stubby, Zanzibar). Dynamo from Amazon. Leslie Lamport's guide on TLA+. The two generals problem, distributed consensus, and so on.
Most distributed systems don't need all that fancy stuff, but it's useful to know regardless. Even the simplest systems will get weird and interesting bottlenecks with scale.
And then a lot of just doing it in practice! Find a job at a startup with some scale, and learn on the job.
Off the top of my head: a lot of stuff from Google (Dapper, Stubby, Zanzibar). Dynamo from Amazon. Leslie Lamport's guide on TLA+. The two generals problem, distributed consensus, and so on.
Most distributed systems don't need all that fancy stuff, but it's useful to know regardless. Even the simplest systems will get weird and interesting bottlenecks with scale.
And then a lot of just doing it in practice! Find a job at a startup with some scale, and learn on the job.