SQS — alert when the dead-letter queue grows
Main SQS queue is processing fine, but the DLQ silently grows — some messages fail 3 attempts and end up there. Nobody looks at the DLQ until it's a thousand deep.
Recipe
#!/usr/bin/env bash
# /etc/cron.d/sqs-dlq
# */5 * * * * root /opt/sqs-dlq.sh
QUEUE=${DLQ_URL}
REGION=${AWS_REGION:-us-east-1}
THRESH=${THRESH:-10} # alert above N messages
DEPTH=$(aws sqs get-queue-attributes \
--region "$REGION" \
--queue-url "$QUEUE" \
--attribute-names ApproximateNumberOfMessages \
--output text --query 'Attributes.ApproximateNumberOfMessages')
if [ "${DEPTH:-0}" -gt "$THRESH" ]; then
curl -fsS "$HEARTBEAT_URL" --data "dlq=$DEPTH,threshold=$THRESH"
exit 2
fi
echo "OK (DLQ=$DEPTH)"Same thing in Enterno.io
Wire to an Enterno heartbeat — see the daily pattern (DLQ drains at night when someone manually replays) or a sudden jump at release time.
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