# KeepAlive

Published articles for KeepAlive.

This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles.

## 【etcd】Lease 与 KeepAlive：TTL、checkpoint 与 Leader 切换

DevFeed: [【etcd】Lease 与 KeepAlive：TTL、checkpoint 与 Leader 切换](<https://devfeed.tech/articles/etcd-lease-keepalive-ttl-checkpoint-leader-33992.md>)

Original publisher: [Read original article](<https://quant67.com/post/etcd/10-lease/10-lease.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>), [Kubernetes](<https://devfeed.tech/topics/kubernetes.md>), [Remote Procedure Call (RPC)](<https://devfeed.tech/topics/rpc.md>)

Tags: [api](<https://devfeed.tech/tags/api.md>), [checkpoint](<https://devfeed.tech/tags/checkpoint.md>), [client](<https://devfeed.tech/tags/client.md>), [concurrency](<https://devfeed.tech/tags/concurrency.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>), [lessor](<https://devfeed.tech/tags/lessor.md>), [primary](<https://devfeed.tech/tags/primary.md>), [raft](<https://devfeed.tech/tags/raft.md>), [ttl](<https://devfeed.tech/tags/ttl.md>), [v3](<https://devfeed.tech/tags/v3.md>), [v3-5-33](<https://devfeed.tech/tags/v3-5-33.md>), [watch](<https://devfeed.tech/tags/watch.md>)

### AI overview

This article explains etcd v3.5.33 lease behavior, focusing on the lessor's primary, demote, and promote roles, the KeepAlive renewal path that normally bypasses Raft, lease checkpointing, and TTL changes during leader transitions. It also discusses implications for Kubernetes Node Leases and distributed locks.

### Source excerpt

钉 etcd v3.5.33 lessor 的 primary/demote/promote、KeepAlive 不经 Raft 的 Renew 路径、LeaseCheckpoint 与 Promote 时 TTL 展期，以及 Leader 切换对 Node Lease 的排障落格。

## 【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。

## 【etcd】排障五轴：Raft/WAL/MVCC/Watch/Lease 口令表

DevFeed: [【etcd】排障五轴：Raft/WAL/MVCC/Watch/Lease 口令表](<https://devfeed.tech/articles/etcd-raft-wal-mvcc-watch-lease-33997.md>)

Original publisher: [Read original article](<https://quant67.com/post/etcd/15-troubleshoot/15-troubleshoot.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>), [Kubernetes](<https://devfeed.tech/topics/kubernetes.md>)

Tags: [apiserver](<https://devfeed.tech/tags/apiserver.md>), [applied-index](<https://devfeed.tech/tags/applied-index.md>), [apply](<https://devfeed.tech/tags/apply.md>), [committed-index](<https://devfeed.tech/tags/committed-index.md>), [compaction](<https://devfeed.tech/tags/compaction.md>), [distributed](<https://devfeed.tech/tags/distributed.md>), [errcompacted](<https://devfeed.tech/tags/errcompacted.md>), [etcd](<https://devfeed.tech/tags/etcd.md>), [five-axes](<https://devfeed.tech/tags/five-axes.md>), [incident](<https://devfeed.tech/tags/incident.md>), [keepalive](<https://devfeed.tech/tags/keepalive.md>), [kubernetes](<https://devfeed.tech/tags/kubernetes.md>), [lag](<https://devfeed.tech/tags/lag.md>), [lease](<https://devfeed.tech/tags/lease.md>), [mvcc](<https://devfeed.tech/tags/mvcc.md>), [node-lease](<https://devfeed.tech/tags/node-lease.md>), [raft](<https://devfeed.tech/tags/raft.md>), [restore](<https://devfeed.tech/tags/restore.md>), [troubleshooting](<https://devfeed.tech/tags/troubleshooting.md>), [ttl](<https://devfeed.tech/tags/ttl.md>), [v3](<https://devfeed.tech/tags/v3.md>), [v3-5](<https://devfeed.tech/tags/v3-5.md>), [v3-5-33](<https://devfeed.tech/tags/v3-5-33.md>), [wal](<https://devfeed.tech/tags/wal.md>), [watch](<https://devfeed.tech/tags/watch.md>)

### AI overview

This troubleshooting article organizes etcd failures into five diagnostic axes: Raft consensus, WAL persistence and recovery, MVCC storage and capacity, Watch client synchronization, and Lease TTL semantics. It maps symptoms to axes, explains relevant etcdctl health and status fields, and notes Kubernetes control-plane relationships, including apiserver and Node Lease behavior. The article is anchored to etcd v3.5.33.

### Source excerpt

按 Raft、WAL、MVCC、Watch、Lease 五轴做症状否证；解释 etcdctl endpoint status/health 字段语义；并对照 K8s 控制面 apiserver 超时与 Node Lease 漂移。