Ask HN: What are good resources for learning about enterprise infrastructure?

I work for a company that works in the PaaS space. My role isn't specifically in the infrastructure area, but I feel like growing my knowledge and understanding of enterprise infrastructure (on-prem datacenters, hybrid cloud, enterprise networking, computing & networking virtualization, etc) will help me be more effective in my work. I've tried to search for good resources online, but there's so much SEO-optimized sales content and bits and pieces of knowledge spread out, that I haven't been able to do some focused reading and learning. Hoping you all can help!