3.4. 监控 etcd 的共识延迟

流程

1. 输入以下命令：

   # oc get pods -n openshift-etcd -l app=etcd

   输出示例

   NAME      READY   STATUS    RESTARTS   AGE
   etcd-m0   4/4     Running   4          8h
   etcd-m1   4/4     Running   4          8h
   etcd-m2   4/4     Running   4          8h

2. 输入以下命令。为了更好地了解 etcd 延迟，您可以精确的监视循环运行这个命令，以等待数字低于 ~66 ms 阈值。更接近的共识时间为 100 毫秒，集群可能会遇到服务影响事件和不稳定的情况。

   # oc exec -ti etcd-m0 -- etcdctl endpoint health -w table

   输出示例

   +----------------------------+--------+-------------+-------+
   |          ENDPOINT          | HEALTH |    TOOK     | ERROR |
   +----------------------------+--------+-------------+-------+
   | https://198.18.111.12:2379 |   true |  3.798349ms |       |
   | https://198.18.111.14:2379 |   true |  7.389608ms |       |
   | https://198.18.111.13:2379 |   true |  6.263117ms |       |
   +----------------------------+--------+-------------+-------+

3. 输入以下命令：

   # oc exec -ti etcd-m0 -- watch -dp -c etcdctl endpoint health -w table

   输出示例

   +----------------------------+--------+-------------+-------+
   |          ENDPOINT          | HEALTH |    TOOK     | ERROR |
   +----------------------------+--------+-------------+-------+
   | https://198.18.111.12:2379 |   true |  9.533405ms |       |
   | https://198.18.111.13:2379 |   true |  4.628054ms |       |
   | https://198.18.111.14:2379 |   true |  5.803378ms |       |
   +----------------------------+--------+-------------+-------+