title: Scripts executed multiple times running on Google Managed VM's
body: <p>I'm fairly new at google cloud and node. Based on Google's recommendation (the requirement to watch Firebase at all times) I deployed managed VM node app, instead of just app engine. There are now 22-23 instances every time I deploy. Is this expected? I thought it would only scale when necessary.</p>
  
  <p>This node app has a method which watches Firebase variables and change, in turn, the script fires off a notification. </p>
  
  <p>What happens now is that multiple notifications are being fired and I only expect one. I suspect it's because there are multiple instances of this app. </p>
  
  <p>What is the right way to do this so that only one is watching?</p>
  
  <p>Thanks.</p>