Send the CONTINUE lifecycle hook so the ASG knows our EC2 came up successfully. This allows ASG launches to continue successfully if the UserData is unsuccessful.

aws-ec2-lifecycle-continue.sh

#!/bin/bash -x
# Send the CONTINUE lifecycle hook so the ASG knows our EC2 came up successfully.
# If the CONTINUE fails, don't care, assume it already was continued

REGION="us-east-1"

INSTANCE_ID=$1
if [ -z $INSTANCE_ID ] ; then echo Specify INSTANCE_ID ; exit 1; fi

ASG_NAME=`aws --output text --region $REGION autoscaling describe-auto-scaling-instances --query 'AutoScalingInstances[?InstanceId==\`'$INSTANCE_ID'\`].AutoScalingGroupName|[0]'`
if [ -z $ASG_NAME ] ; then echo Could not get ASG_NAME ; exit 1; fi

LIFECYCLE_HOOK_NAME=`aws --region $REGION autoscaling describe-lifecycle-hooks --auto-scaling-group-name ${ASG_NAME} --query 'LifecycleHooks[].LifecycleHookName' --output text`
if [ -z $LIFECYCLE_HOOK_NAME ] ; then echo Could not get LIFECYCLE_HOOK_NAME ; exit 1; fi

echo "# REGION=$REGION INSTANCE_ID=$INSTANCE_ID ASG_NAME=$ASG_NAME LIFECYCLE_HOOK_NAME=$LIFECYCLE_HOOK_NAME"

aws autoscaling complete-lifecycle-action --region $REGION --instance-id $INSTANCE_ID --lifecycle-hook-name $LIFECYCLE_HOOK_NAME --auto-scaling-group-name $ASG_NAME --lifecycle-action-result CONTINUE 

if [ $? -ne 0 ]
then
    echo WARNING Failed to send complete-lifecycle-action CONTINUE
fi