"Cross-Cloud"
- AWS SQS → Google Pub/Sub:queue 模型搬到 topic + subscription 模型的跨雲遷移
SQS 是單一 region-scoped pull queue、Pub/Sub 是 global topic + first-class subscription 的 pub/sub 模型;這篇跨雲 migration playbook 走 6 維 diff dimension audit(components / data topology 軸 High)、對位 visibility timeout → ack deadline、maxReceiveCount → dead-letter topic、long polling → streaming pull、IAM policy → Service Account、SQS-to-many-consumer 要重設計成 topic fan-out;含 5 個 production 故障演練(fan-out 行為差 / ack deadline 太短重投 / ordering key vs FIFO / 跨雲網路成本 / DLT 設定差)跟 dual-publish 漸進 cutover