Where is the meshConfig stored

When we execute the command like described in this tutorial,

istioctl install --set meshConfig.accessLogFile=/dev/stdout

Where is the meshConfig actually stored? Is there a config file / db that holds the meshConfig in the infra containers or on the host where istioctl is?

Also instead of directing the logs to /dev/stdout, is it possible to pipe it to a third party endpoint via syslog or https?

kubectl -n istio-system get cm istio -o yaml