由于测试的需要，有时需要搭建一个单机版的etcd 环境，为了方便以后搭建查看，现在对单机部署进行记录。
一、部署单机etcd
- 下载 指定版本的etcd
下载地址ftp://ftp.pbone.net/mirror/archive.fedoraproject.org/fedora/linux/updates/22/x86_64/e/etcd-2.2.5-1.fc22.x86_64.rpm
先判断是否已经安装了etcd，已经安装的话就需要先删除掉，注意权限问题
[vagrant@localhost wae]$ yum list installed | grep etcd etcd.x86_64 2.2.0-1.el7 installed [vagrant@localhost wae]$ yum remove etcd.x86_64 Loaded plugins: fastestmirror You need to be root to perform this command. [vagrant@localhost wae]$ sudo yum remove etcd.x86_64 Loaded plugins: fastestmirror Resolving Dependencies --> Running transaction check ---> Package etcd.x86_64 0:2.2.0-1.el7 will be erased --> Finished Dependency Resolution Dependencies Resolved =================================================================================================== Package Arch Version Repository Size =================================================================================================== Removing: etcd x86_64 2.2.0-1.el7 installed 26 M Transaction Summary =================================================================================================== Remove 1 Package Installed size: 26 M Is this ok [y/N]: y Downloading packages: Running transaction check Running transaction test Transaction test succeeded Running transaction Erasing : etcd-2.2.0-1.el7.x86_64 1/1 warning: /etc/etcd/etcd.conf saved as /etc/etcd/etcd.conf.rpmsave Verifying : etcd-2.2.0-1.el7.x86_64 1/1 Removed: etcd.x86_64 0:2.2.0-1.el7 Complete!
安装下载的rpm包
[vagrant@localhost etcd]$ sudo yum localinstall etcd-2.2.5-1.fc22.x86_64.rpm
验证安装成功
[vagrant@localhost etcd]$ etcdctl --version etcdctl version 2.2.5
- 创建一个服务描述文件，放入systemd的服务目录下，一般安装完成都会自动创建
[vagrant@localhost etcd]$ sudo vi /usr/lib/systemd/system/etcd.service [Unit] Description=Etcd Server After=network.target After=network-online.target Wants=network-online.target [Service] Type=notify WorkingDirectory=/var/lib/etcd/ EnvironmentFile=-/etc/etcd/etcd.conf User=etcd # set GOMAXPROCS to number of processors ExecStart=/bin/bash -c "GOMAXPROCS=$(nproc) /usr/bin/etcd --name="${ETCD_NAME}" --data-dir="${ETCD_DATA_DIR}" --listen-client-urls="${ETCD_LISTEN_CLIENT_URLS}"" Restart=on-failure LimitNOFILE=65536 [Install] WantedBy=multi-user.target
- 修改etcd的配置
一般默认访问的地址是http://localhost:2379，这边我们可以自定义，因为是单机，我们就直接127.0.0.1，有想法的就端口修改下好了[vagrant@localhost etcd]$ sudo vi /etc/etcd/etcd.conf# [member]
ETCD_NAME=default
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
#ETCD_WAL_DIR=""
#ETCD_SNAPSHOT_COUNT="10000"
#ETCD_HEARTBEAT_INTERVAL="100"
#ETCD_ELECTION_TIMEOUT="1000"
#ETCD_LISTEN_PEER_URLS="http://localhost:2380"
ETCD_LISTEN_CLIENT_URLS="http://127.0.0.1:4001"
#ETCD_MAX_SNAPSHOTS="5"
#ETCD_MAX_WALS="5"
#ETCD_CORS=""
#
#[cluster]
#ETCD_INITIAL_ADVERTISE_PEER_URLS="http://localhost:2380"
# if you use different ETCD_NAME (e.g. test), set ETCD_INITIAL_CLUSTER value for this name, i.e. "test=http://..."
#ETCD_INITIAL_CLUSTER="default=http://localhost:2380"
#ETCD_INITIAL_CLUSTER_STATE="new"
#ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster"
ETCD_ADVERTISE_CLIENT_URLS="http://127.0.0.1:4001"
#ETCD_DISCOVERY=""
#ETCD_DISCOVERY_SRV=""
#ETCD_DISCOVERY_FALLBACK="proxy"
#ETCD_DISCOVERY_PROXY=""
#
#[proxy]
#ETCD_PROXY="off"
#ETCD_PROXY_FAILURE_WAIT="5000"
#ETCD_PROXY_REFRESH_INTERVAL="30000"
#ETCD_PROXY_DIAL_TIMEOUT="1000"
#ETCD_PROXY_WRITE_TIMEOUT="5000"
#ETCD_PROXY_READ_TIMEOUT="0"
#
#[security]
#ETCD_CERT_FILE=""
#ETCD_KEY_FILE=""
#ETCD_CLIENT_CERT_AUTH="false"
#ETCD_TRUSTED_CA_FILE=""
#ETCD_PEER_CERT_FILE=""
#ETCD_PEER_KEY_FILE=""
#ETCD_PEER_CLIENT_CERT_AUTH="false"
#ETCD_PEER_TRUSTED_CA_FILE=""
#
#[logging]
#ETCD_DEBUG="false"
# examples for -log-package-levels etcdserver=WARNING,security=DEBUG
#ETCD_LOG_PACKAGE_LEVELS=""如果想要局域网可以访问的话，则将 127.0.0.1 换成宿主机的 ip 即可了，最后外部用 ip 进行接口访问即可。
- 启动并测试ETCD
首先设置开机启动：systemctl enable etcd
[vagrant@localhost etcd]$ sudo systemctl daemon-reload [vagrant@localhost etcd]$ sudo systemctl start etcd [vagrant@localhost etcd]$ sudo systemctl status etcd ● etcd.service - Etcd Server Loaded: loaded (/usr/lib/systemd/system/etcd.service; disabled; vendor preset: disabled) Active: active (running) since Fri 2018-03-09 08:55:47 UTC; 8s ago Main PID: 4624 (etcd) Memory: 26.0M CGroup: /system.slice/etcd.service └─4624 /usr/bin/etcd --name=default --data-dir=/var/lib/etcd/default.etcd --listen-cl... Mar 09 08:55:46 localhost.localdomain systemd[1]: Starting Etcd Server... Mar 09 08:55:47 localhost.localdomain systemd[1]: Started Etcd Server.
查看集群健康状态
[vagrant@localhost etcd]$ sudo etcdctl cluster-health member ce2a822cea30bfca is healthy: got healthy result from http://127.0.0.1:4001 cluster is healthy
ok，没有问题
- 卸载与删除etcd
[vagrant@localhost wae]$ yum list installed | grep etcd etcd.x86_64 2.2.0-1.el7 installed [vagrant@localhost wae]$ yum remove etcd.x86_64
二、接口测试
etcd的数据形式是以健对值方式存在的。
- 通过接口获取版本信息
[vagrant@localhost etcd]$ curl http://127.0.0.1:4001/version -XGET {"etcdserver":"2.2.5","etcdcluster":"2.2.0"}
- 更新一个健对值信息，并通过 ke y获取到 value
[vagrant@localhost etcd]$ etcdctl set /tmp/message wozainali wozainali [vagrant@localhost etcd]$ etcdctl get /tmp/message wozainali
设置的方式：etcdctl set key value
获取的方式：etcdctl get key - 通过接口获取健对值信息
[vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XGET {"action":"get","node":{"key":"/tmp/message","value":"wozainali","modifiedIndex":12,"createdIndex":12}}
再看看 详细的请求信息
[vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XGET {"action":"get","node":{"key":"/tmp/message","value":"wozainali","modifiedIndex":12,"createdIndex":12}} [vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XGET -vv * About to connect() to 127.0.0.1 port 4001 (#0) * Trying 127.0.0.1... * Connected to 127.0.0.1 (127.0.0.1) port 4001 (#0) > GET /v2/keys/tmp/message HTTP/1.1 > User-Agent: curl/7.29.0 > Host: 127.0.0.1:4001 > Accept: */* > < HTTP/1.1 200 OK < Content-Type: application/json < X-Etcd-Cluster-Id: 7e27652122e8b2ae < X-Etcd-Index: 12 < X-Raft-Index: 37173 < X-Raft-Term: 3 < Date: Fri, 09 Mar 2018 09:16:15 GMT < Content-Length: 104 < {"action":"get","node":{"key":"/tmp/message","value":"wozainali","modifiedIndex":12,"createdIndex":12}} * Connection #0 to host 127.0.0.1 left intact
- 通过接口更新一个健对值信息
[vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XPUT -d value=nihaoha {"action":"set","node":{"key":"/tmp/message","value":"nihaoha","modifiedIndex":13,"createdIndex":13},"prevNode":{"key":"/tmp/message","value":"wozainali","modifiedIndex":12,"createdIndex":12}} [vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XGET {"action":"get","node":{"key":"/tmp/message","value":"nihaoha","modifiedIndex":13,"createdIndex":13}}
我们看到更新的时候，会有两条记录，一条是当前记录，一条是之前的记录，多次更新也只会保留最近的信息，获取的时候默认获取最新的信息
[vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XPUT -d value=wowowow {"action":"set","node":{"key":"/tmp/message","value":"wowowow","modifiedIndex":14,"createdIndex":14},"prevNode":{"key":"/tmp/message","value":"nihaoha","modifiedIndex":13,"createdIndex":13}}
具体复杂的操作需要去看官方文档，这边只做了解使用。https://coreos.com/etcd/docs/latest/v2/api.html
- 通过接口删除健对值信息
[vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XDELETE {"action":"delete","node":{"key":"/tmp/message","modifiedIndex":15,"createdIndex":14},"prevNode":{"key":"/tmp/message","value":"wowowow","modifiedIndex":14,"createdIndex":14}} [vagrant@localhost etcd]$ curl http://127.0.0.1:4001/v2/keys/tmp/message -XGET {"errorCode":100,"message":"Key not found","cause":"/tmp/message","index":15}
可以看到删除之后，重新去获取该 key 的值，提示Key not found，证明我们删除成功了。
以上就是，简单的指定etcd单机安装，以及api的几个简单应用。
三、问题
- 在修改访问ip问局域网ip之后发现，使用 etcdctl 进行操作的时候会出现如下错误
[vagrant@localhost etcd]$ etcdctl ls Error: dial tcp 127.0.0.1:4001: getsockopt: connection refused [vagrant@localhost etcd]$ [vagrant@localhost etcd]$ [vagrant@localhost etcd]$ etcdctl cluster-health cluster may be unhealthy: failed to list members Error: client: etcd cluster is unavailable or misconfigured error #0: dial tcp 127.0.0.1:4001: getsockopt: connection refused error #1: dial tcp 127.0.0.1:2379: getsockopt: connection refused
查询之后，发现应该是 ETCD_LISTEN_CLIENT_URLS 没有写入 http://127.0.0.1:4001 的原因，追加配置 http://127.0.0.1:4001，重新试一下
[vagrant@localhost etcd]$ etcdctl ls /test /test123 /tmp /test1223 [vagrant@localhost etcd]$ etcdctl cluster-health member ce2a822cea30bfca is healthy: got healthy result from http://192.168.10.50:4001 cluster is healthy [vagrant@localhost etcd]$
现在就可以了。
注意，添加配置的时候，用英文的逗号隔开.