Consul入门

来源：互联网发布：程序员到底是做什么的编辑：程序博客网时间：2024/06/04 19:57

参考文档：

https://www.consul.io/intro/index.html

备注：采用版本Consul v1.0.0

目录
consul介绍

consul安装

运行代理

关闭代理

注册服务

consul集群

健康检查

KV数据

WebUI

gossip协议

一致性协议： https://www.consul.io/docs/internals/consensus.html

一、consul介绍

服务发现

健康检查

KV存储

多数据中心

二、安装

windows系统：

1、下载安装包

https://www.consul.io/downloads.html

2、配置路径

解压zip

执行文件拷贝到C:\\consul\\bin

配置环境变量：path C:\TDM-GCC-64\bin;C:\consul\bin;C:\Gradle\gradle-3.5\bin;%JAVA_HOME%\bin;%HADOOP_HOME%\bin;%M2_HOME%\bin;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files\Intel\WiFi\bin\;C:\ProgramData\Oracle\Java\javapath;C:\Program Files\Common Files\Intel\WirelessCommon\;C:\ProgramData\Anaconda3;C:\ProgramData\Anaconda3\Scripts;C:\ProgramData\Anaconda3\Library\bin;C:\TDM-GCC-64\bin;C:\Program Files\Git\cmd;%GROOVY_HOME%\bin

3、测试安装

C:\Windows\system32>consul --version
Consul v0.8.1

Protocol 2 spoken by default, understands 2 to 3 (agent will automatically use protocol >2 when speaking to compatible agents)

ubuntu系统：

consul直接拷贝到： /usr/local/bin

三、运行代理

启动一个代理

C:\Windows\system32>consul agent -dev
==> Starting Consul agent...
==> Consul agent running!
           Version: 'v0.8.1'
           Node ID: '6edb8e08-d606-4650-a196-fff5632843f9'
         Node name: 'DESKTOP-QHG7SFL'
        Datacenter: 'dc1'
            Server: true (bootstrap: false)
       Client Addr: 127.0.0.1 (HTTP: 8500, HTTPS: -1, DNS: 8600)
      Cluster Addr: 127.0.0.1 (LAN: 8301, WAN: 8302)
    Gossip encrypt: false, RPC-TLS: false, TLS-Incoming: false
             Atlas: <disabled>

==> Log data will now stream in as it occurs:

    2017/11/06 09:06:38 [DEBUG] Using unique ID "6edb8e08-d606-4650-a196-fff5632843f9" from host as node ID

查看集群成员

新打卡一个窗口

查看成员信息

C:\Windows\system32>consul members
Node Address Status Type Build Protocol DC
DESKTOP-QHG7SFL 127.0.0.1:8301 alive server 0.8.1 2 dc1

C:\Windows\system32>curl localhost:8500/v1/catalog/nodes
[
    {
        "ID": "6edb8e08-d606-4650-a196-fff5632843f9",
        "Node": "DESKTOP-QHG7SFL",
        "Address": "127.0.0.1",
        "TaggedAddresses": {
            "lan": "127.0.0.1",
            "wan": "127.0.0.1"
        },
        "Meta": {},
        "CreateIndex": 5,
        "ModifyIndex": 6
    }
]

四、关闭代理

强制关闭： ctrl - c

一致性：不要强制性关闭

五、注册服务

1、服务定义的方式注册服务

创建配置文件

$ sudo mkdir /etc/consul.d

$echo '{"service": {"name": "web", "tags": ["rails"], "port": 80}}' > | sudo tee /etc/consul.d/web.json

重启代理

$ consul agent -dev -config-dir=/etc/consul.d
    ==> Starting Consul agent...
    ==> Consul agent running!
           Version: 'v1.0.0'
           Node ID: 'b1a78817-513c-1dbd-cf57-d3602f503764'
         Node name: 'slave-01'
        Datacenter: 'dc1' (Segment: '<all>')
            Server: true (Bootstrap: false)
       Client Addr: [127.0.0.1] (HTTP: 8500, HTTPS: -1, DNS: 860

2、DNS访问服务

   $ dig @127.0.0.1 -p 8600 web.service.consul

; <<>> DiG 9.10.3-P4-Ubuntu <<>> @127.0.0.1 -p 8600 web.service.consul
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56299
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;web.service.consul.       IN   A

;; ANSWER SECTION:
web.service.consul.   0   IN   A   127.0.0.1

;; Query time: 0 msec
;; SERVER: 127.0.0.1#8600(127.0.0.1)
;; WHEN: Tue Nov 07 05:53:38 CST 2017
;; MSG SIZE rcvd: 63

use the DNS API to retrieve the entire address/port pair as a SRV record:

$ dig @127.0.0.1 -p 8600 web.service.consul SRV

; <<>> DiG 9.10.3-P4-Ubuntu <<>> @127.0.0.1 -p 8600 web.service.consul SRV
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62764
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 3
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;web.service.consul.       IN   SRV

;; ANSWER SECTION:
web.service.consul.   0   IN   SRV   1 1 80 slave-01.node.dc1.consul.

;; ADDITIONAL SECTION:
slave-01.node.dc1.consul. 0   IN   A   127.0.0.1
slave-01.node.dc1.consul. 0   IN   TXT   "consul-network-segment="

;; Query time: 0 msec
;; SERVER: 127.0.0.1#8600(127.0.0.1)
;; WHEN: Tue Nov 07 05:55:21 CST 2017
;; MSG SIZE rcvd: 143

3、Http访问服务

$ curl http://localhost:8500/v1/catalog/service/web
[
    {
        "ID": "b1a78817-513c-1dbd-cf57-d3602f503764",
        "Node": "slave-01",
        "Address": "127.0.0.1",
        "Datacenter": "dc1",
        "TaggedAddresses": {
            "lan": "127.0.0.1",
            "wan": "127.0.0.1"
        },
        "NodeMeta": {
            "consul-network-segment": ""
        },
        "ServiceID": "web",
        "ServiceName": "web",
        "ServiceTags": [
            "rails"
        ],
        "ServiceAddress": "",
        "ServicePort": 80,
        "ServiceEnableTagOverride": false,
        "CreateIndex": 6,
        "ModifyIndex": 6
    }
]

只访问健康实例：

$ curl 'http://localhost:8500/v1/health/service/web?passing'
[
    {
        "Node": {
            "ID": "b1a78817-513c-1dbd-cf57-d3602f503764",
            "Node": "slave-01",
            "Address": "127.0.0.1",
            "Datacenter": "dc1",
            "TaggedAddresses": {
                "lan": "127.0.0.1",
                "wan": "127.0.0.1"
            },
            "Meta": {
                "consul-network-segment": ""
            },
            "CreateIndex": 5,
            "ModifyIndex": 6
        },
        "Service": {
            "ID": "web",
            "Service": "web",
            "Tags": [
                "rails"
            ],
            "Address": "",
            "Port": 80,
            "EnableTagOverride": false,
            "CreateIndex": 6,
            "ModifyIndex": 6
        },
        "Checks": [
            {
                "Node": "slave-01",
                "CheckID": "serfHealth",
                "Name": "Serf Health Status",
                "Status": "passing",
                "Notes": "",
                "Output": "Agent alive and reachable",
                "ServiceID": "",
                "ServiceName": "",
                "ServiceTags": [],
                "CreateIndex": 5,
                "ModifyIndex": 5
            }
        ]
    }
]

4、更新服务

1> consul可以在服务提供的时候动态修改状态

2> 更新服务方法

修改配置文件，并发送SIGHUP给代理

HTTP API

六、Consul集群

1、启动server

注意： -ui参数打开web ui

      $ consul agent -server -bootstrap-expect=1     -data-dir=/tmp/consul -node=agent-one -bind=192.168.1.190 -ui -enable-script-checks=true -config-dir=/etc/consul.d
BootstrapExpect is set to 1; this is the same as Bootstrap mode.
bootstrap = true: do not enable unless necessary
==> Starting Consul agent...
==> Consul agent running!
           Version: 'v1.0.0'
           Node ID: '51006970-7f03-de36-12fb-dcd7dd0ecdee'
         Node name: 'agent-one'
        Datacenter: 'dc1' (Segment: '<all>')
            Server: true (Bootstrap: true)
       Client Addr: [127.0.0.1] (HTTP: 8500, HTTPS: -1, DNS: 8600)
      Cluster Addr: 192.168.1.190 (LAN: 8301, WAN: 8302)
           Encrypt: Gossip: false, TLS-Outgoing: false, TLS-Incoming: false

--node name：节点名称

-bootstrap-expect: 期望服务数码

--data-dir: 节点存储数据的目录

-enable-script-checks：健康检查

-config-dir: 配置文件所在目录

2、启动代理

$ consul agent -data-dir=/tmp/consul -node=agent-two -bind=192.168.1.191 -enable-script-checks=true -config-dir=/etc/consul.d
==> Starting Consul agent...
==> Consul agent running!
           Version: 'v1.0.0'
           Node ID: 'bdf166e5-9ffd-4f0f-d513-9010b2d318d8'
         Node name: 'agent-two'
        Datacenter: 'dc1' (Segment: '')
            Server: false (Bootstrap: false)
       Client Addr: [127.0.0.1] (HTTP: 8500, HTTPS: -1, DNS: 8600)
      Cluster Addr: 192.168.1.191 (LAN: 8301, WAN: 8302)
           Encrypt: Gossip: false, TLS-Outgoing: false, TLS-Incoming: false

3、加入集群

   lxq@slave-01:/data$ consul join 192.168.1.191
     Successfully joined cluster by contacting 1 nodes.
   lxq@slave-01:/data$ consul members
       Node       Address             Status Type    Build Protocol DC   Segment
       agent-one 192.168.1.190:8301 alive   server 1.0.0 2         dc1 <all>
       agent-two 192.168.1.191:8301 alive   client 1.0.0 2         dc1 <default>

注： consul代理加入集群，只需加入一个存在的成员就可以了。

4、自动加入集群

add the retry_join_ec2, retry_join_gce or the retry_join_azure nested object to your Consul configuration file

5、访问节点

     lxq@slave-01:/data$ dig @127.0.0.1 -p 8600 agent-two.node.consul

; <<>> DiG 9.10.3-P4-Ubuntu <<>> @127.0.0.1 -p 8600 agent-two.node.consul
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27975
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;agent-two.node.consul.       IN   A

;; ANSWER SECTION:
agent-two.node.consul.   0   IN   A   192.168.1.191

;; Query time: 0 msec
;; SERVER: 127.0.0.1#8600(127.0.0.1)
;; WHEN: Tue Nov 07 07:57:56 CST 2017
;; MSG SIZE rcvd: 66

6、离开集群

1> 强制离开 Ctrl-C

2> 优雅离开

运行节点转为离开状态

七、健康检查——需要研究下，与教程结果不符

1、定义检查

30s运行一次ping操作，检查google网站的健康：

root@slave-02:/home/lxq# echo '{"check": {"name": "ping",
>   "script": "ping -c1 google.com >/dev/null", "interval": "30s"}}' \
>   >/etc/consul.d/ping.json
root@slave-02:/home/lxq# echo '{"service": {"name": "web", "tags": ["rails"], "port": 80,
>   "check": {"script": "curl localhost >/dev/null 2>&1", "interval": "10s"}}}' \
>   >/etc/consul.d/web.json

10s运行一次检查本地webserver的健康：

root@slave-02:/home/lxq# cat /etc/consul.d/
ping.json web.json
root@slave-02:/home/lxq# cat /etc/consul.d/web.json
{"service": {"name": "web", "tags": ["rails"], "port": 80,
"check": {"script": "curl localhost >/dev/null 2>&1", "interval": "10s"}}}
2、检查健康状态
root@slave-02:/home/lxq# curl http://localhost:8500/v1/health/state/critical
[]

root@slave-02:/home/lxq# dig @127.0.0.1 -p 8600 web.service.consul

; <<>> DiG 9.10.3-P4-Ubuntu <<>> @127.0.0.1 -p 8600 web.service.consul
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 8183
;; flags: qr aa rd; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;web.service.consul.       IN   A

;; ANSWER SECTION:
web.service.consul.   0   IN   A   192.168.1.191
web.service.consul.   0   IN   A   192.168.1.190

;; Query time: 1 msec
;; SERVER: 127.0.0.1#8600(127.0.0.1)
;; WHEN: Tue Nov 07 08:20:45 CST 2017
;; MSG SIZE rcvd: 79

八、KV Data

用处：动态配置，帮助协调服务，领导选取

方式： Consul kv cli, Consul KV HTTP API

1、写入

root@slave-02:/home/lxq# consul kv get redis/config/minconns
Error! No key exists at: redis/config/minconns

root@slave-02:/home/lxq# consul kv put redis/config/minconns 1
Success! Data written to: redis/config/minconns
root@slave-02:/home/lxq# consul kv put redis/config/maxconns 25
Success! Data written to: redis/config/maxconns
root@slave-02:/home/lxq# consul kv put -flags=42 redis/config/users/admin abcd1234
Success! Data written to: redis/config/users/admin

2、读取

读取一个键值对：

root@slave-02:/home/lxq# consul kv get redis/config/minconns
1

root@slave-02:/home/lxq# consul kv get -detailed redis/config/minconns
CreateIndex      560
Flags            0
Key              redis/config/minconns
LockIndex        0
ModifyIndex      560
Session          -
Value            1

读取所有的键值对：

root@slave-02:/home/lxq# consul kv get -recurse
redis/config/maxconns:25
redis/config/minconns:1
redis/config/users/admin:abcd1234

3、删除

删除一个键

root@slave-02:/home/lxq# consul kv delete redis/config/minconns
Success! Deleted key: redis/config/minconns

删除所有redis开头的键
root@slave-02:/home/lxq# consul kv delete -recurse redis
Success! Deleted keys with prefix: redis

4、cas设置——与教程不一致

root@slave-02:/home/lxq# consul kv put foo bar
Success! Data written to: foo
root@slave-02:/home/lxq# consul kv get foo
bar
root@slave-02:/home/lxq# consul kv put foo zip
Success! Data written to: foo
root@slave-02:/home/lxq# consul kv get foo
zip

root@slave-02:/home/lxq# consul kv put -cas -modify-index=123 foo bar
Error! Did not write to foo: CAS failed
root@slave-02:/home/lxq# consul kv put -cas -modify-index=123 foo bar
Error! Did not write to foo: CAS failed

九、Web UI

consul agent -ui

http://localhost:8500/ui

阅读全文

0 0