I've started to use Google Cloud Platform and I got some troubles understanding how it works.
Here's what I've done so far :
I've created an Google Compute Instance using Wordpress Click-to-deploy image
I've made a snapshot of this instance
I've made an image from this snapshot
I've made an instance template with this image
I've made a instance group based on this template
I've created a load-balancer using this instance group
Everything's working fine : I can access my website.
For what I've understood so far is that each instance created by the group is "independant" : I've put differents PHP scripts inside each instance (like 'echo "1" ' in instance 1 and 'echo "2" ' in instance 2) and "each" time I refresh the page, it displays '1' or '2'
Here's my problem : If I want to add a post or to update the WP (like adding a plugin or editing the CSS), in which instance should I do it ?