amazon web services - React on initialization errors for ec2 autoscale instances -


i have webserver running on ec2 behind elb scaled using aws autoscale. when new instance starts fetches recent application code git repository.

what's best way react on errors during initialization?

  • git server might not up/reachable
  • disk might corrupt, git pull exists error (yes has happened me)

this did:

  • on start create file instance_starting
  • once initialization finished delete file
  • the elb health check accesses special url returns error 500 if instance_starting file exists
  • a cloudwatch alarm reports me unhealthy instances

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