Results 3 issues of Liu BoFan

**What happened**: HostAliases not working if pod network is set to hostNetwork **What you expected to happen**: HostAliases is injected to `/etc/hosts` correctly in hostNetowork mode. **How to reproduce it...

kind/bug

**What would you like to be added/modified**: Support cross-subnet pod communication **Why is this needed**: It's common that cloud node can not reach edge node behind NAT. So It is...

kind/feature

It took me some time to find out what exactly `instance:node_cpu:ratio` metirc is. It seems cpu and memory metric is come from [helm-charts/charts/kube-prometheus-stack/templates/prometheus/rules/kube-prometheus-node-recording.rules.yaml](https://github.com/prometheus-community/helm-charts/blob/c4a7d10fdc6a0f694d9b97e9446207ba67d997dd/charts/kube-prometheus-stack/templates/prometheus/rules/kube-prometheus-node-recording.rules.yaml) rule which is is removed and seems...