# 案例三：扩/缩容异常-故障现象

+ 某套集群进行 TiKV 节点的下线操作，但此节点一直处于 offline 状态。
![center](./student-guide/diagram/place-holder.png)

  + offline-peer-region-count
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    - 下线某个 TiKV 节点后，一直处于 offline 状态，查看 PD -> Region health 监控指标，发现始终有 1 个 offline-peer-region-count ：The number of Regions during the offline process