Ask HN: How to prepare for Google/Facebook SRE interviews?

I am a devops engineer at a startup and am good at my job. I do everything from automation to distributed systems, AWS, CI/CD, troubleshooting, etc.

My colleagues and founder are very happy with my performance. However, when I research on the kind of questions asked in google SRE interview, I start having self-doubts. I am not sure how much depth is expected from me in each of the areas like troubleshooting, scripting, networking etc. Ex: for troubleshooting, should I know all the syscalls and the definition and be fully comfortable with strace?

It will be great if I can get some guidance on how and how much to prepare for these areas:

Linux internals

Troubleshooting

Large System design

Scripting

Networking

I am reading the books on Linux kernel development, Operating systems, networking. How much depth should I have to ace the interviews?