Certainly very common in my company. After 1 year in my team, I'm still discovering services we're supporting that I've never heard of! But being oncall doesn'

Certainly very common in my company. After 1 year in my team, I'm still discovering services we're supporting that I've never heard of! But being oncall doesn't mean that you're supposed to fix every single issue by yourself. You're allowed to ask for help! Monitoring the alerts, taking care of some simple issues (broken CI), trying to fix what you can, and dispatching when you can't. This is usually doable by a new team member.