Linux版本
uname -a
Linux etcd1 3.10.0-1062.9.1.el7.x86_64 #1 SMP Fri Dec 6 15:49:49 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
三个节点
cat /etc/hosts
192.168.1.66 etcd1
192.168.1.67 etcd2
192.168.1.68 etcd3
关闭防火墙
systemctl stop firewalld
systemctl disable firewalld
安装etcd。
yum install -y etcd
配置etcd1：
#[Member]
#ETCD_CORS=""
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
#ETCD_WAL_DIR=""
ETCD_LISTEN_PEER_URLS="http://0.0.0.0:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379,http://0.0.0.0:4001"
#ETCD_MAX_SNAPSHOTS="5"
#ETCD_MAX_WALS="5"
ETCD_NAME="etcd1"
#ETCD_SNAPSHOT_COUNT="100000"
#ETCD_HEARTBEAT_INTERVAL="100"
#ETCD_ELECTION_TIMEOUT="1000"
#ETCD_QUOTA_BACKEND_BYTES="0"
#ETCD_MAX_REQUEST_BYTES="1572864"
#ETCD_GRPC_KEEPALIVE_MIN_TIME="5s"
#ETCD_GRPC_KEEPALIVE_INTERVAL="2h0m0s"
#ETCD_GRPC_KEEPALIVE_TIMEOUT="20s"
#
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.1.66:2380"
ETCD_ADVERTISE_CLIENT_URLS="http://192.168.1.66:2379,http://192.168.1.66:4001"
#ETCD_DISCOVERY=""
#ETCD_DISCOVERY_FALLBACK="proxy"
#ETCD_DISCOVERY_PROXY=""
#ETCD_DISCOVERY_SRV=""
ETCD_INITIAL_CLUSTER="etcd1=http://192.168.1.66:2380,etcd2=http://192.168.1.67:2380,etcd3=http://192.168.1.68:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-twingao-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
#ETCD_STRICT_RECONFIG_CHECK="true"
#ETCD_ENABLE_V2="true"
配置etcd2：
#[Member]
#ETCD_CORS=""
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
#ETCD_WAL_DIR=""
ETCD_LISTEN_PEER_URLS="http://0.0.0.0:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379,http://0.0.0.0:4001"
#ETCD_MAX_SNAPSHOTS="5"
#ETCD_MAX_WALS="5"
ETCD_NAME="etcd2"
#ETCD_SNAPSHOT_COUNT="100000"
#ETCD_HEARTBEAT_INTERVAL="100"
#ETCD_ELECTION_TIMEOUT="1000"
#ETCD_QUOTA_BACKEND_BYTES="0"
#ETCD_MAX_REQUEST_BYTES="1572864"
#ETCD_GRPC_KEEPALIVE_MIN_TIME="5s"
#ETCD_GRPC_KEEPALIVE_INTERVAL="2h0m0s"
#ETCD_GRPC_KEEPALIVE_TIMEOUT="20s"
#
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.1.67:2380"
ETCD_ADVERTISE_CLIENT_URLS="http://192.168.1.67:2379,http://192.168.1.67:4001"
#ETCD_DISCOVERY=""
#ETCD_DISCOVERY_FALLBACK="proxy"
#ETCD_DISCOVERY_PROXY=""
#ETCD_DISCOVERY_SRV=""
ETCD_INITIAL_CLUSTER="etcd1=http://192.168.1.66:2380,etcd2=http://192.168.1.67:2380,etcd3=http://192.168.1.68:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-twingao-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
#ETCD_STRICT_RECONFIG_CHECK="true"
#ETCD_ENABLE_V2="true"
配置etcd3：
#[Member]
#ETCD_CORS=""
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
#ETCD_WAL_DIR=""
ETCD_LISTEN_PEER_URLS="http://0.0.0.0:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379,http://0.0.0.0:4001"
#ETCD_MAX_SNAPSHOTS="5"
#ETCD_MAX_WALS="5"
ETCD_NAME="etcd3"
#ETCD_SNAPSHOT_COUNT="100000"
#ETCD_HEARTBEAT_INTERVAL="100"
#ETCD_ELECTION_TIMEOUT="1000"
#ETCD_QUOTA_BACKEND_BYTES="0"
#ETCD_MAX_REQUEST_BYTES="1572864"
#ETCD_GRPC_KEEPALIVE_MIN_TIME="5s"
#ETCD_GRPC_KEEPALIVE_INTERVAL="2h0m0s"
#ETCD_GRPC_KEEPALIVE_TIMEOUT="20s"
#
#[Clustering]
ETCD_INITIAL_ADVERTISE_PEER_URLS="http://192.168.1.68:2380"
ETCD_ADVERTISE_CLIENT_URLS="http://192.168.1.68:2379,http://192.168.1.68:4001"
#ETCD_DISCOVERY=""
#ETCD_DISCOVERY_FALLBACK="proxy"
#ETCD_DISCOVERY_PROXY=""
#ETCD_DISCOVERY_SRV=""
ETCD_INITIAL_CLUSTER="etcd1=http://192.168.1.66:2380,etcd2=http://192.168.1.67:2380,etcd3=http://192.168.1.68:2380"
ETCD_INITIAL_CLUSTER_TOKEN="etcd-twingao-cluster"
ETCD_INITIAL_CLUSTER_STATE="new"
#ETCD_STRICT_RECONFIG_CHECK="true"
#ETCD_ENABLE_V2="true"
参数说明：
ETCD_DATA_DIR：数据存储目录
ETCD_LISTEN_PEER_URLS：与其他节点通信时的监听地址列表，通信协议可以是http、https
ETCD_LISTEN_CLIENT_URLS：与客户端通信时的监听地址列表
ETCD_NAME：节点名称
ETCD_INITIAL_ADVERTISE_PEER_URLS：节点在整个集群中的通信地址列表，可以理解为能与外部通信的ip端口
ETCD_ADVERTISE_CLIENT_URLS：告知集群中其他成员自己名下的客户端的地址列表
ETCD_INITIAL_CLUSTER：集群内所有成员的地址，这就是为什么称之为静态发现，因为所有成员的地址都必须配置
ETCD_INITIAL_CLUSTER_TOKEN：初始化集群口令，用于标识不同集群
ETCD_INITIAL_CLUSTER_STATE：初始化集群状态，new表示新建
启动etcd服务，并配置自启动。
systemctl start etcd
systemctl enable etcd
如果不能启动etcd服务，可以删除所有节点/var/lib/etcd目录下内容，然后重新启动。
查看etcd版本。
etcd --version
etcd Version: 3.3.11
Git SHA: 2cf9e51
Go Version: go1.10.3
Go OS/Arch: linux/amd64
查看etcdctl版本。
etcdctl --version
etcdctl version: 3.3.11
API version: 2
etcd api分为2和3版本，其对应的命令行客户端etcdctl也有两种版本模式，两个版本在使用上有些区别，从上面的命令看安装后etcd api缺省是2版本，采用如下方法可以改为3版本。
vi /etc/profile
export ETCDCTL_API=3
source /etc/profile
查看集群节点：
etcdctl member list
3bfc158cf02dfab9, started, etcd3, http://192.168.1.68:2380, http://192.168.1.68:2379,http://192.168.1.68:4001
8835dd4fc48bb08a, started, etcd2, http://192.168.1.67:2380, http://192.168.1.67:2379,http://192.168.1.67:4001
fbe83a7120c1fef4, started, etcd1, http://192.168.1.66:2380, http://192.168.1.66:2379,http://192.168.1.66:4001
在etcd1节点停止etcd服务，再查看集群，发现无法连接，因为etcdctl缺省访问本地的etcd服务。
systemctl stop etcd
etcdctl member list
Error: dial tcp 127.0.0.1:2379: connect: connection refused
在命令行指定endpoint，etcdctl可以向其他endpoint请求数据，防止一个节点出故障导致集群无法访问。
etcdctl --endpoints=192.168.1.66:2379,192.168.1.67:2379,192.168.1.68:2379 member list
3bfc158cf02dfab9, started, etcd3, http://192.168.1.68:2380, http://192.168.1.68:2379,http://192.168.1.68:4001
8835dd4fc48bb08a, started, etcd2, http://192.168.1.67:2380, http://192.168.1.67:2379,http://192.168.1.67:4001
fbe83a7120c1fef4, started, etcd1, http://192.168.1.66:2380, http://192.168.1.66:2379,http://192.168.1.66:4001
查看endpoint的状态。
etcdctl --endpoints=192.168.1.66:2379,192.168.1.67:2379,192.168.1.68:2379 endpoint status
Failed to get the status of endpoint 192.168.1.66:2379 (context deadline exceeded)
192.168.1.67:2379, 8835dd4fc48bb08a, 3.3.11, 20 kB, false, 16, 20
192.168.1.68:2379, 3bfc158cf02dfab9, 3.3.11, 20 kB, true, 16, 20
endpoint健康检查。
etcdctl --endpoints=192.168.1.66:2379,192.168.1.67:2379,192.168.1.68:2379 endpoint health
192.168.1.68:2379 is healthy: successfully committed proposal: took = 6.832804ms
192.168.1.67:2379 is healthy: successfully committed proposal: took = 10.387798ms
192.168.1.66:2379 is unhealthy: failed to connect: dial tcp 192.168.1.66:2379: connect: connection refused
Error: unhealthy cluster
etcdctl支持的3版本的命令。
etcdctl
NAME:
etcdctl - A simple command line client for etcd3.
USAGE:
etcdctl
VERSION:
3.3.11
API VERSION:
3.3
COMMANDS:
get Gets the key or a range of keys
put Puts the given key into the store
del Removes the specified key or range of keys [key, range_end)
txn Txn processes all the requests in one transaction
compaction Compacts the event history in etcd
alarm disarm Disarms all alarms
alarm list Lists all alarms
defrag Defragments the storage of the etcd members with given endpoints
endpoint health Checks the healthiness of endpoints specified in `--endpoints` flag
endpoint status Prints out the status of endpoints specified in `--endpoints` flag
endpoint hashkv Prints the KV history hash for each endpoint in --endpoints
move-leader Transfers leadership to another etcd cluster member.
watch Watches events stream on keys or prefixes
version Prints the version of etcdctl
lease grant Creates leases
lease revoke Revokes leases
lease timetolive Get lease information
lease list List all active leases
lease keep-alive Keeps leases alive (renew)
member add Adds a member into the cluster
member remove Removes a member from the cluster
member update Updates a member in the cluster
member list Lists all members in the cluster
snapshot save Stores an etcd node backend snapshot to a given file
snapshot restore Restores an etcd member snapshot to an etcd directory
snapshot status Gets backend snapshot status of a given file
make-mirror Makes a mirror at the destination etcd cluster
migrate Migrates keys in a v2 store to a mvcc store
lock Acquires a named lock
elect Observes and participates in leader election
auth enable Enables authentication
auth disable Disables authentication
user add Adds a new user
user delete Deletes a user
user get Gets detailed information of a user
user list Lists all users
user passwd Changes password of user
user grant-role Grants a role to a user
user revoke-role Revokes a role from a user
role add Adds a new role
role delete Deletes a role
role get Gets detailed information of a role
role list Lists all roles
role grant-permission Grants a key to a role
role revoke-permission Revokes a key from a role
check perf Check the performance of the etcd cluster
help Help about any command
OPTIONS:
--cacert="" verify certificates of TLS-enabled secure servers using this CA bundle
--cert="" identify secure client using this TLS certificate file
--command-timeout=5s timeout for short running command (excluding dial timeout)
--debug[=false] enable client-side debug logging
--dial-timeout=2s dial timeout for client connections
-d, --discovery-srv="" domain name to query for SRV records describing cluster endpoints
--endpoints=[127.0.0.1:2379] gRPC endpoints
-h, --help[=false] help for etcdctl
--hex[=false] print byte strings as hex encoded strings
--insecure-discovery[=true] accept insecure SRV records describing cluster endpoints
--insecure-skip-tls-verify[=false] skip server certificate verification
--insecure-transport[=true] disable transport security for client connections
--keepalive-time=2s keepalive time for client connections
--keepalive-timeout=6s keepalive timeout for client connections
--key="" identify secure client using this TLS key file
--user="" username[:password] for authentication (prompt if password is not supplied)
-w, --write-out="simple" set the output format (fields, json, protobuf, simple, table)
创建key
etcdctl put hello world
OK
查询给定key的值。第一行为key，第二行为value。
etcdctl get hello
hello
world
在etcd1节点监听key hello值的变化，该命令会一直等待。
etcdctl watch hello
在etcd2节点修改该key的值。
etcdctl put hello world!
OK
在etcd1节点监听命令立马就有反馈。
etcdctl watch hello
PUT
hello
world!
先增加几个key。
etcdctl put hello1 nihao
OK
etcdctl put hello2 ninhao
OK
基于key前缀查找。
etcdctl get hello --prefix
hello
world!
hello1
nihao
hello2
ninhao
查找所有的key值。
etcdctl put key1 value1
OK
etcdctl get "" --prefix
hello
world!
hello1
nihao
hello2
ninhao
key1
value1