VSCode search exclude using multiple regex

 To exclude the files when doing a search in VSCode, one can specify multiple regular expressions in a string like this.

vendor/**,**/*_test.go

The above will exclude all the files under vendor folder and all the files whose name ends with _test.go

How to use computer to control your devices

 To use a computer to control (Power on/off) many devices, one may use a system like this.

1.  Connect a multi-channel Relay module to a computer via possibly RS485 interface. Something like this.

Modbus RTU 8-Channels Relay Module with RS485 Bus

2. Then use low voltage wire to connect a device via solid state relay to the multi-channel relay. Something like this:

3. Then create a program to manage the multiple channel relay to control device's power.

4. It may be necessary to have a converter for RS485 so that the multi-channel relay can be connected with a computer (PC)

Istio secrets

 Istiod uses serviceAccount `istiod` and serviceAccountName `istiod` to have gain access to k8s api server. According to how service account works with a pod, this basically mount the token in this directory

/var/run/secrets/kubernetes.io/serviceaccount

this directory contains root ca, namespace and jwt.

in remote case, istiod has to be configured to use istio-kubeconfig secret to gain access to the remote cluster. The secret will be mounted to istiod pod at the following location

/var/run/secrets/remote

the name of the file normally is config which basically contains a content of a kube config file.