rebuf VS etcd

Etcd is a key value store for all cluster data. It is an etcd data store. So, It is highly available, reliable, and distributed.

Look at the code for the watcher client[1] and lease management[2].

[1]: https://github.com/etcd-io/etcd/blob/main/client/v3/watch.go

[2]: https://github.com/etcd-io/etcd/blob/main/client/v3/lease.go

Did I miss it or is there no call to os.File.Sync() anywhere?

Since you mention etcd/wal:

https://github.com/etcd-io/etcd/blob/v3.3.27/wal/wal.go#L671

https://github.com/etcd-io/etcd/blob/v3.3.27/pkg/fileutil/sy...

raftexample is an example provided by etcd that demonstrates the use of the etcd raft consensus algorithm library. raftexample ultimately implements a distributed key-value storage service that provides a REST API.

There's the etcdctl tool that allows to interact with etcd, if you know exactly what you're looking for, and how this is stored in etcd, etc. But expecting our users to do this for upgrading? Meh...

The open source projects Fastly uses and the foundations we partner with are vital to Fastly’s mission and success. Here's an unscientific list of projects and organizations supported by the Linux Foundation that we use and love include: The Linux Kernel, Kubernetes, containerd, eBPF, Falco, OpenAPI Initiative, ESLint, Express, Fastify, Lodash, Mocha, Node.js, Prometheus, Jenkins, OpenTelemetry, Envoy, etcd, Helm, osquery, Harbor, sigstore, cert-manager, Cilium, Fluentd, Keycloak, Open Policy Agent, Coalition for Content Provenance and Authority (C2PA), Flux, gRPC, Strimzi, Thanos, Linkerd, Let’s Encrypt, WebAssembly. And the list goes on!

Each time we create or update a K8s resource, the Kubernetes API stores it in its database — etcd. etcd is a distributed key-value store used to store all of your resource configurations, such as deployments, services, and so on. A neat feature of etcd is that you can subscribe to changes in some keys in the database, which is used by other Kubernetes mechanisms.

so far, we have been able to do some fault simulation tests by using the fault points built in etcd. how to use these fault points can refer to the official integration test implementation of etcd-> etcd Robustness Testing. you can search for relevant codes by the name of the fault point.