常用

基本使用-一个Agent的开发模式

# Agent的开发模式:

[root@local13 ~]# ./consul agent -dev
==> Starting Consul agent...
==> Consul agent running!

# 查看集群成员:

[root@local13 ~]# ./consul members
Node     Address         Status  Type    Build  Protocol  DC   Segment
local13  127.0.0.1:8301  alive   server  1.2.2  2         dc1  <all>

# 使用 HTTP API 查看:

[root@local13 ~]# curl localhost:8500/v1/catalog/nodes
[
    {
        "ID": "796b14fe-1332-4aa0-d96f-8f287a4ccc7e",
        "Node": "local13",
        "Address": "127.0.0.1",
        "Datacenter": "dc1",
        "TaggedAddresses": {
            "lan": "127.0.0.1",
            "wan": "127.0.0.1"
        },
        "Meta": {
            "consul-network-segment": ""
        },
        "CreateIndex": 9,
        "ModifyIndex": 10
    }
]

# 还可以使用 DNS 接口来查询节点(默认端口:8600:

[root@local13 ~]# yum install bind-utils
[root@local13 ~]# dig @127.0.0.1 -p 8600 local13.node.consul
...
;; QUESTION SECTION:
;local13.node.consul.       IN  A
;; ANSWER SECTION:
local13.node.consul.    0   IN  A   127.0.0.1
...

注册服务

定义一个服务:

[root@local13 ~]# mkdir /etc/consul.d
[root@local13 ~]# echo '{"service": {"name": "web", "tags": ["rails"], "port": 80}}'  | sudo tee /etc/consul.d/web.json
[root@local13 ~]# ./consul agent -dev -config-dir=/etc/consul.d

# 使用 DNS API:

[root@local13 ~]# dig @127.0.0.1 -p 8600 web.service.consul
...
;; QUESTION SECTION:
;web.service.consul.        IN  A
;; ANSWER SECTION:
web.service.consul. 0   IN  A   127.0.0.1

# 使用 DNS API 查找 SRV 记录:

[root@local13 ~]# dig @127.0.0.1 -p 8600 web.service.consul SRV
...
;; QUESTION SECTION:
;web.service.consul.        IN  SRV
;; ANSWER SECTION:
web.service.consul. 0   IN  SRV 1 1 80 local13.node.dc1.consul.
;; ADDITIONAL SECTION:
local13.node.dc1.consul. 0  IN  A   127.0.0.1
...

# 使用 HTTP API 查询:

[root@local13 ~]# curl http://localhost:8500/v1/catalog/service/web
# 健康检查
[root@local13 ~]# curl 'http://localhost:8500/v1/health/service/web?passing'

Consul集群

创建node1,consul server:

[root@local12 ~]# ./consul agent \
-server \
-bootstrap-expect=1  \
-data-dir=/tmp/consul \
-node=agent-one \
-bind=192.168.56.112 \
-enable-script-checks=true \
-config-dir=/etc/consul.d \
-client 0.0.0.0 \
-ui
# -node: 节点的名称
# -bind: 绑定的一个地址,用于节点之间通信的地址
# -server: 这个就是表示这个节点是个SERVER
# -bootstrap-expect: 这个就是表示期望提供的SERVER节点数目,数目一达到就会被激活,生成LEADER
# -dc: 指明数据中心的名字
# -client 0.0.0.0
# -ui: 启动UI(为了方便后续的UI访问)

创建node2,consul client:

[root@local13 ~]# ./consul agent -data-dir=/tmp/consul \
-node=agent-two   \
-bind=192.168.56.113 -enable-script-checks=true \
-config-dir=/etc/consul.d \
-ui

加入集群:

[root@local13 ~]# ./consul join 192.168.56.112
Successfully joined cluster by contacting 1 nodes.
[root@local13 ~]# ./consul members
Node       Address            Status  Type    Build  Protocol  DC   Segment
agent-one  192.168.1.13:8301  alive   server  1.2.2  2         dc1  <all>
agent-two  192.168.1.12:8301  alive   client  1.2.2  2         dc1  <default>

查询节点:

[root@local13 ~]# dig @127.0.0.1 -p 8600 agent-two.node.consul
...
;; QUESTION SECTION:
;agent-two.node.consul.     IN  A
;; ANSWER SECTION:
agent-two.node.consul.  0   IN  A   192.168.1.12

KV数据

基本操作:

consul kv put redis/config/minconns 1
consul kv put redis/config/minconns 2 # 更新
consul kv get redis/config/minconns
consul kv delete redis/config/minconns
consul kv delete -recurse redis # 批量删除