README
¶
etcd
Note: The master branch may be in an unstable or even broken state during development. Please use releases instead of the master branch in order to get stable binaries.
etcd is a distributed, consistent key-value store for shared configuration and service discovery, with a focus on being:
- Simple: curl'able user-facing API (HTTP+JSON)
- Secure: optional SSL client cert authentication
- Fast: benchmarked 1000s of writes/s per instance
- Reliable: properly distributed using Raft
etcd is written in Go and uses the Raft consensus algorithm to manage a highly-available replicated log.
etcd is used in production by many companies, and the development team stands behind it in critical deployment scenarios, where etcd is frequently teamed with applications such as Kubernetes, fleet, locksmith, vulcand, and many others.
See etcdctl for a simple command line client.
Or feel free to just use curl, as in the examples below.
Getting Started
Getting etcd
The easiest way to get etcd is to use one of the pre-built release binaries which are available for OSX, Linux, Windows, AppC (ACI), and Docker. Instructions for using these binaries are on the GitHub releases page.
For those wanting to try the very latest version, you can build the latest version of etcd from the master branch.
You will first need Go installed on your machine (version 1.5+ is required).
All development occurs on master, including new features and bug fixes.
Bug fixes are first targeted at master and subsequently ported to release branches, as described in the branch management guide.
Running etcd
First start a single-member cluster of etcd:
./bin/etcd
This will bring up etcd listening on port 2379 for client communication and on port 2380 for server-to-server communication.
Next, let's set a single key, and then retrieve it:
curl -L http://127.0.0.1:2379/v2/keys/mykey -XPUT -d value="this is awesome"
curl -L http://127.0.0.1:2379/v2/keys/mykey
You have successfully started an etcd and written a key to the store.
etcd TCP ports
The official etcd ports are 2379 for client requests, and 2380 for peer communication. To maintain compatibility, some etcd configuration and documentation continues to refer to the legacy ports 4001 and 7001, but all new etcd use and discussion should adopt the IANA-assigned ports. The legacy ports 4001 and 7001 will be fully deprecated, and support for their use removed, in future etcd releases.
Running local etcd cluster
First install goreman, which manages Procfile-based applications.
Our Procfile script will set up a local example cluster. You can start it with:
goreman start
This will bring up 3 etcd members infra1, infra2 and infra3 and etcd proxy proxy, which runs locally and composes a cluster.
You can write a key to the cluster and retrieve the value back from any member or proxy.
Next Steps
Now it's time to dig into the full etcd API and other guides.
- Explore the full API.
- Set up a multi-machine cluster.
- Learn the config format, env variables and flags.
- Find language bindings and tools.
- Use TLS to secure an etcd cluster.
- Tune etcd.
- Upgrade from 0.4.9+ to 2.2.0.
Contact
- Mailing list: etcd-dev
- IRC: #etcd on freenode.org
- Planning/Roadmap: milestones, roadmap
- Bugs: issues
Contributing
See CONTRIBUTING for details on submitting patches and the contribution workflow.
Reporting bugs
See reporting bugs for details about reporting any issue you may encounter.
Project Details
Versioning
Service Versioning
etcd uses semantic versioning New minor versions may add additional features to the API.
You can get the version of etcd by issuing a request to /version:
curl -L http://127.0.0.1:2379/version
API Versioning
The v2 API responses should not change after the 2.0.0 release but new features will be added over time.
32-bit and other unsupported systems
etcd has known issues on 32-bit systems due to a bug in the Go runtime. See #358 for more information.
To avoid inadvertantly running a possibly unstable etcd server, etcd on unsupported architectures will print
a warning message and immediately exit if the environment variable ETCD_UNSUPPORTED_ARCH is not set to
the target architecture.
Currently only the amd64 architecture is officially supported by etcd.
License
etcd is under the Apache 2.0 license. See the LICENSE file for details.
Documentation
¶
Overview ¶
Package main is a simple wrapper of the real etcd entrypoint package (located at github.com/coreos/etcd/etcdmain) to ensure that etcd is still "go getable"; e.g. `go get github.com/coreos/etcd` works as expected and builds a binary in $GOBIN/etcd
This package should NOT be extended or modified in any way; to modify the etcd binary, work in the `github.com/coreos/etcd/etcdmain` package.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
Package alarm manages health status alarms in etcd.
|
Package alarm manages health status alarms in etcd. |
|
authpb
Package authpb is a generated protocol buffer package.
|
Package authpb is a generated protocol buffer package. |
|
Package client provides bindings for the etcd APIs.
|
Package client provides bindings for the etcd APIs. |
|
Package clientv3 implements the official Go etcd client for v3.
|
Package clientv3 implements the official Go etcd client for v3. |
|
concurrency
Package concurrency implements concurrency operations on top of etcd such as distributed locks, barriers, and elections.
|
Package concurrency implements concurrency operations on top of etcd such as distributed locks, barriers, and elections. |
|
integration
Package integration implements tests built upon embedded etcd, and focuses on correctness of etcd client.
|
Package integration implements tests built upon embedded etcd, and focuses on correctness of etcd client. |
|
mirror
Package mirror implements etcd mirroring operations.
|
Package mirror implements etcd mirroring operations. |
|
contrib
|
|
|
Package discovery provides an implementation of the cluster discovery that is used by etcd.
|
Package discovery provides an implementation of the cluster discovery that is used by etcd. |
|
Package e2e implements tests built upon etcd binaries, and focus on end-to-end testing.
|
Package e2e implements tests built upon etcd binaries, and focus on end-to-end testing. |
|
Package error describes errors in etcd project.
|
Package error describes errors in etcd project. |
|
etcdctl is a command line application that controls etcd.
|
etcdctl is a command line application that controls etcd. |
|
ctlv2
Package ctlv2 contains the main entry point for the etcdctl for v2 API.
|
Package ctlv2 contains the main entry point for the etcdctl for v2 API. |
|
ctlv2/command
Package command is a set of libraries for etcdctl commands.
|
Package command is a set of libraries for etcdctl commands. |
|
ctlv3
Package ctlv3 contains the main entry point for the etcdctl for v3 API.
|
Package ctlv3 contains the main entry point for the etcdctl for v3 API. |
|
ctlv3/command
Package command is a set of libraries for etcd v3 commands.
|
Package command is a set of libraries for etcd v3 commands. |
|
Package etcdmain contains the main entry point for the etcd binary.
|
Package etcdmain contains the main entry point for the etcd binary. |
|
Package etcdserver defines how etcd servers interact and store their states.
|
Package etcdserver defines how etcd servers interact and store their states. |
|
api/v2http
Package v2http provides etcd client and server implementations.
|
Package v2http provides etcd client and server implementations. |
|
api/v2http/httptypes
Package httptypes defines how etcd's HTTP API entities are serialized to and deserialized from JSON.
|
Package httptypes defines how etcd's HTTP API entities are serialized to and deserialized from JSON. |
|
api/v3rpc
Package v3rpc implements etcd v3 RPC system based on gRPC.
|
Package v3rpc implements etcd v3 RPC system based on gRPC. |
|
auth
Package auth implements etcd authentication.
|
Package auth implements etcd authentication. |
|
etcdserverpb
Package etcdserverpb is a generated protocol buffer package.
|
Package etcdserverpb is a generated protocol buffer package. |
|
stats
Package stats defines a standard interface for etcd cluster statistics.
|
Package stats defines a standard interface for etcd cluster statistics. |
|
Package integration implements tests built upon embedded etcd, and focus on etcd correctness.
|
Package integration implements tests built upon embedded etcd, and focus on etcd correctness. |
|
leasepb
Package leasepb is a generated protocol buffer package.
|
Package leasepb is a generated protocol buffer package. |
|
pkg
|
|
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cors
Package cors handles cross-origin HTTP requests (CORS).
|
Package cors handles cross-origin HTTP requests (CORS). |
|
crc
Package crc provides utility function for cyclic redundancy check algorithms.
|
Package crc provides utility function for cyclic redundancy check algorithms. |
|
expect
Package expect implements a small expect-style interface
|
Package expect implements a small expect-style interface |
|
fileutil
Package fileutil implements utility functions related to files and paths.
|
Package fileutil implements utility functions related to files and paths. |
|
flags
Package flags implements command-line flag parsing.
|
Package flags implements command-line flag parsing. |
|
httputil
Package httputil provides HTTP utility functions.
|
Package httputil provides HTTP utility functions. |
|
idutil
Package idutil implements utility functions for generating unique, randomized ids.
|
Package idutil implements utility functions for generating unique, randomized ids. |
|
ioutil
Package ioutil implements I/O utility functions.
|
Package ioutil implements I/O utility functions. |
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logutil
Package logutil includes utilities to facilitate logging.
|
Package logutil includes utilities to facilitate logging. |
|
netutil
Package netutil implements network-related utility functions.
|
Package netutil implements network-related utility functions. |
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osutil
Package osutil implements operating system-related utility functions.
|
Package osutil implements operating system-related utility functions. |
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pathutil
Package pathutil implements utility functions for handling slash-separated paths.
|
Package pathutil implements utility functions for handling slash-separated paths. |
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pbutil
Package pbutil defines interfaces for handling Protocol Buffer objects.
|
Package pbutil defines interfaces for handling Protocol Buffer objects. |
|
runtime
Package runtime implements utility functions for runtime systems.
|
Package runtime implements utility functions for runtime systems. |
|
testutil
Package testutil provides test utility functions.
|
Package testutil provides test utility functions. |
|
transport
Package transport implements various HTTP transport utilities based on Go net package.
|
Package transport implements various HTTP transport utilities based on Go net package. |
|
types
Package types declares various data types and implements type-checking functions.
|
Package types declares various data types and implements type-checking functions. |
|
wait
Package wait provides utility functions for polling, listening using Go channel.
|
Package wait provides utility functions for polling, listening using Go channel. |
|
proxy
|
|
|
httpproxy
Package httpproxy implements etcd httpproxy.
|
Package httpproxy implements etcd httpproxy. |
|
Package raft sends and receives messages in the Protocol Buffer format defined in the raftpb package.
|
Package raft sends and receives messages in the Protocol Buffer format defined in the raftpb package. |
|
raftpb
Package raftpb is a generated protocol buffer package.
|
Package raftpb is a generated protocol buffer package. |
|
rafttest
Package rafttest provides functional tests for etcd's raft implementation.
|
Package rafttest provides functional tests for etcd's raft implementation. |
|
Package rafthttp implements HTTP transportation layer for etcd/raft pkg.
|
Package rafthttp implements HTTP transportation layer for etcd/raft pkg. |
|
Package snap stores raft nodes' states with snapshots.
|
Package snap stores raft nodes' states with snapshots. |
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snappb
Package snappb is a generated protocol buffer package.
|
Package snappb is a generated protocol buffer package. |
|
Package storage defines etcd's stable storage.
|
Package storage defines etcd's stable storage. |
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backend
Package backend defines a standard interface for etcd's backend storage.
|
Package backend defines a standard interface for etcd's backend storage. |
|
storagepb
Package storagepb is a generated protocol buffer package.
|
Package storagepb is a generated protocol buffer package. |
|
Package store defines etcd's in-memory key/value store.
|
Package store defines etcd's in-memory key/value store. |
|
tools
|
|
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Package version implements etcd version parsing and contains latest version information.
|
Package version implements etcd version parsing and contains latest version information. |
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Package wal provides an implementation of a write ahead log that is used by etcd.
|
Package wal provides an implementation of a write ahead log that is used by etcd. |
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walpb
Package walpb is a generated protocol buffer package.
|
Package walpb is a generated protocol buffer package. |