AWS WAIT command

Wait for …


When writing shell scripts by using the CLI there will be the need to wait for a specific condition from time to time. For example, after initiating an EBS snapshot your script might need to wait until the snapshot was completed. Waiting can be achieved with a polling loop and a describe-* command. But there is a simpler solution built into the CLI for this: aws <service> wait <condition>.

The following contains a wait command that will block the script until the snapshot has been completed.

#!/bin/bash
echo "Waiting for EBS snapshot"
aws ec2 wait snapshot-completed --snapshot-ids snap-id_abc
echo "EBS snapshot completed" 
You'll find many more uses for this, and hopefully no more corruption as commands compete.

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