# 【etcd】读路径与一致性：ReadIndex、Serializable 与 Lease read

DevFeed: [【etcd】读路径与一致性：ReadIndex、Serializable 与 Lease read](<https://devfeed.tech/articles/etcd-readindex-serializable-lease-read-33990.md>)

Original publisher: [Read original article](<https://quant67.com/post/etcd/08-read-consistency/08-read-consistency.html>)

Author: Liao Tonglang

Published: 2026-08-26T00:00:00Z

Content type: tutorial

Language: zh

Sources: [土法炼钢 - 系统与基础设施](<https://devfeed.tech/sources/source-4.md>)

Topics: [etcd](<https://devfeed.tech/topics/etcd.md>), [Raft](<https://devfeed.tech/topics/raft.md>), [consensus algorithm](<https://devfeed.tech/topics/consensus-algorithm.md>), [Kubernetes](<https://devfeed.tech/topics/kubernetes.md>)

Tags: [consistency](<https://devfeed.tech/tags/consistency.md>), [distributed](<https://devfeed.tech/tags/distributed.md>), [etcd](<https://devfeed.tech/tags/etcd.md>), [follower](<https://devfeed.tech/tags/follower.md>), [k8s](<https://devfeed.tech/tags/k8s.md>), [keepalive](<https://devfeed.tech/tags/keepalive.md>), [kubernetes](<https://devfeed.tech/tags/kubernetes.md>), [lease](<https://devfeed.tech/tags/lease.md>), [linearizable](<https://devfeed.tech/tags/linearizable.md>), [raft](<https://devfeed.tech/tags/raft.md>), [readindex](<https://devfeed.tech/tags/readindex.md>), [resourceversion](<https://devfeed.tech/tags/resourceversion.md>), [revision](<https://devfeed.tech/tags/revision.md>), [serializable](<https://devfeed.tech/tags/serializable.md>), [ttl](<https://devfeed.tech/tags/ttl.md>), [v3-5](<https://devfeed.tech/tags/v3-5.md>), [v3-5-33](<https://devfeed.tech/tags/v3-5-33.md>)

## AI overview

This tutorial explains read consistency in etcd v3.5.33. It distinguishes default linearizable reads using ReadIndex, local Serializable reads that may be stale on followers, and Lease RPC reads handled by the leader outside the Raft log. It also discusses leader changes, apply-index waiting, follower forwarding, MVCC history reads, and implications for Kubernetes apiserver clients.

## Source excerpt

分列 etcd v3.5.33 三种读语义：默认线性一致读的 ReadIndex 循环、Serializable 本地读、Raft ReadOnlyLeaseBased 与不经 Raft 的 Lease 路径；follower 读风险与 K8s 期望。