1、RabbitMQ介绍
RabbitMQ
是实现了高级消息队列协议AMQP
的开源消息代理软件(亦称面向消息的中间件)。RabbitMQ
服务器是用Erlang
语言编写的,而集群和故障转移是构建在开放电信平台框架上的。AMQP
:Advanced Message Queue
,高级消息队列协议。它是应用层协议的一个开放标准,为面向消息的中间件设计,基于此协议的客户端与消息中间件可传递消息,并不受产品、开发语言灯条件的限制
AMQP
具有如下的特性:
- 可靠性
Reliablity
:使用了一些机制来保证可靠性,比如持久化、传输确认、发布确认 - 灵活的路由
Flexible Routing
:在消息进入队列之前,通过Exchange
来路由消息。对于典型的路由功能,Rabbit
已经提供了一些内置的Exchange
来实现。针对更复杂的路由功能,可以将多个Exchange
绑定在一起,也通过插件机制实现自己的Exchange
- 消息集群
Clustering
:多个RabbitMQ
服务器可以组成一个集群,形成一个逻辑Broker
- 高可用
Highly Avaliable Queues
:队列可以在集群中的机器上进行镜像,使得在部分节点出问题的情况下队列仍然可用 - 多种协议
Multi-protocol
:支持多种消息队列协议,如STOMP
、MQTT
等 - 多种语言客户端
Many Clients
:几乎支持所有常用语言,比如Java
、.NET
、Ruby
等 - 管理界面
Management UI
:提供了易用的用户界面,使得用户可以监控和管理消息Broker
的许多方面 - 跟踪机制
Tracing
:如果消息异常,RabbitMQ
提供了消息的跟踪机制,使用者可以找出发生了什么 - 插件机制
Plugin System
:提供了许多插件,来从多方面进行扩展,也可以编辑自己的插件
2、RabbitMQ的持久化和镜像队列
RabbitMQ
持久化分为Exchange
、Queue
、Message
Exchange
和Queue
持久化:指持久化Exchange
、Queue
元数据,持久化的是自身,服务宕机Exchange
和Queue
自身就没有了Message
持久化:顾名思义就是把每一条消息体持久化,服务宕机,消息不丢失
RabbitMQ
的队列Queue
镜像,指master node
在接受到请求后,会同步到其他节点上,以此来保证高可用。在confirm
模式下,具体过程如下
clientpublisher发送消息 –> master node接到消息 –> master node将消息持久化到磁盘 –> 将消息异步发送给其他节点 –> master将ack返回给client publisher
3、RabbitMQ集群在k8s中的部署
将RabbitMQ
以集群的方式部署在k8s
中,前提是RabbitMQ
的每个节点都能像传统方式一样进行相互的服务发现。因此RabbitMQ
在k8s
集群中通过rabbitmq_peer_discovery_k8s plugin
与k8s apiserver
进行交互,获取各个服务的URL
,且RabbitMQ
在k8s
集群中必须用statefulset
和headless service
进行匹配
需要注意的是,rabbitmq_peer_discovery_k8s
是RabbitMQ
官方基于第三方开源项目rabbitmq-autocluster
开发,对3.7.X
及以上版本提供的Kubernetes
下的对等发现插件,可实现rabbitmq
集群在k8s
中的自动化部署,因此低于3.7.X版本请使用rabbitmq-autocluster
3.1 环境介绍
本文部署的版本是3.8.3
默认部署在default
命名空间下,
持久化存储为storageclass
动态存储,底层为nfs
提供
镜像地址rabbitmq:3.8.3-management
以下yaml
参考自官方示例https://github.com/rabbitmq/diy-kubernetes-examples
3.2 创建configmap
01-rabbitmq-configmap.yaml
kind: ConfigMap
apiVersion: v1
metadata:
name: rabbitmq-cluster-config
namespace: default
labels:
addonmanager.kubernetes.io/mode: Reconcile
data:
enabled_plugins: |
[rabbitmq_management,rabbitmq_peer_discovery_k8s].
rabbitmq.conf: |
default_user = admin
default_pass = 123!@#
## Cluster formation. See https://www.rabbitmq.com/cluster-formation.html to learn more.
cluster_formation.peer_discovery_backend = rabbit_peer_discovery_k8s
cluster_formation.k8s.host = kubernetes.default.svc.cluster.local
## Should RabbitMQ node name be computed from the pod's hostname or IP address?
## IP addresses are not stable, so using [stable] hostnames is recommended when possible.
## Set to "hostname" to use pod hostnames.
## When this value is changed, so should the variable used to set the RABBITMQ_NODENAME
## environment variable.
cluster_formation.k8s.address_type = hostname
## How often should node cleanup checks run?
cluster_formation.node_cleanup.interval = 30
## Set to false if automatic removal of unknown/absent nodes
## is desired. This can be dangerous, see
## * https://www.rabbitmq.com/cluster-formation.html#node-health-checks-and-cleanup
## * https://groups.google.com/forum/#!msg/rabbitmq-users/wuOfzEywHXo/k8z_HWIkBgAJ
cluster_formation.node_cleanup.only_log_warning = true
cluster_partition_handling = autoheal
## See https://www.rabbitmq.com/ha.html#master-migration-data-locality
queue_master_locator=min-masters
## See https://www.rabbitmq.com/access-control.html#loopback-users
loopback_users.guest = false
cluster_formation.randomized_startup_delay_range.min = 0
cluster_formation.randomized_startup_delay_range.max = 2
# default is rabbitmq-cluster's namespace
# hostname_suffix
cluster_formation.k8s.hostname_suffix = .rabbitmq-cluster.default.svc.cluster.local
# memory
vm_memory_high_watermark.absolute = 1GB
# disk
disk_free_limit.absolute = 2GB
部分参数说明:
- enabled_plugins:声明开启的插件名
- default_pass/default_pass:声明用户名和密码(虽然有部分文章记录可以通过环境变量的方式声明,但是经测试,针对此版本如果指定了
configmap
即rabbitmq
的配置文件,声明的环境变量是没有用的,都需要在配置文件中指定) - cluster_formation.k8s.address_type:从
k8s
返回的Pod
容器列表中计算对等节点列表,这里只能使用主机名,官方示例中是ip
,但是默认情况下在k8s
中pod
的ip
都是不固定的,因此可能导致节点的配置和数据丢失,后面的yaml
中会通过引用元数据的方式固定pod
的主机名。
更多参数请参考官方文档,这里就不赘述了
3.3 创建service
02-rabbitmq-service.yaml
kind: Service
apiVersion: v1
metadata:
labels:
app: rabbitmq-cluster
name: rabbitmq-cluster
namespace: default
spec:
clusterIP: None
ports:
- name: rmqport
port: 5672
targetPort: 5672
selector:
app: rabbitmq-cluster
---
kind: Service
apiVersion: v1
metadata:
labels:
app: rabbitmq-cluster
name: rabbitmq-cluster-manage
namespace: default
spec:
ports:
- name: http
port: 15672
protocol: TCP
targetPort: 15672
selector:
app: rabbitmq-cluster
type: NodePort
上面定义了两个Service
,一个是rabbitmq
的服务端口,一个是管理界面的端口,用户外部访问,这里通过NodePort
方式进行暴露
3.4 创建rbac授权
前面的介绍中提到了RabbitMQ
通过插件与k8s apiserver交互获得集群中节点相关信息,因此需要对其进行RBAC
授权
03-rabbitmq-rbac.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: rabbitmq-cluster
namespace: default
---
kind: Role
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: rabbitmq-cluster
namespace: default
rules:
- apiGroups: [""]
resources: ["endpoints"]
verbs: ["get"]
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: rabbitmq-cluster
namespace: default
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: rabbitmq-cluster
subjects:
- kind: ServiceAccount
name: rabbitmq-cluster
namespace: default
3.5 创建statefulset
RabbitMQ
在k8s
中作为一个有状态应用进行部署,因此控制器类型为StatefulSet
,yaml
中还定义了pvc
相关内容
04-rabbitmq-cluster-sts.yaml
kind: StatefulSet
apiVersion: apps/v1
metadata:
labels:
app: rabbitmq-cluster
name: rabbitmq-cluster
namespace: default
spec:
replicas: 3
selector:
matchLabels:
app: rabbitmq-cluster
serviceName: rabbitmq-cluster
template:
metadata:
labels:
app: rabbitmq-cluster
spec:
containers:
- args:
- -c
- cp -v /etc/rabbitmq/rabbitmq.conf ${RABBITMQ_CONFIG_FILE}; exec docker-entrypoint.sh
rabbitmq-server
command:
- sh
env:
- name: TZ
value: 'Asia/Shanghai'
- name: RABBITMQ_ERLANG_COOKIE
value: 'SWvCP0Hrqv43NG7GybHC95ntCJKoW8UyNFWnBEWG8TY='
- name: K8S_SERVICE_NAME
value: rabbitmq-cluster
- name: POD_IP
valueFrom:
fieldRef:
fieldPath: status.podIP
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
- name: POD_NAMESPACE
valueFrom:
fieldRef:
fieldPath: metadata.namespace
- name: RABBITMQ_USE_LONGNAME
value: "true"
- name: RABBITMQ_NODENAME
value: rabbit@$(POD_NAME).$(K8S_SERVICE_NAME).$(POD_NAMESPACE).svc.cluster.local
- name: RABBITMQ_CONFIG_FILE
value: /var/lib/rabbitmq/rabbitmq.conf
image: rabbitmq:3.8.3-management
imagePullPolicy: IfNotPresent
livenessProbe:
exec:
command:
- rabbitmq-diagnostics
- status
# See https://www.rabbitmq.com/monitoring.html for monitoring frequency recommendations.
initialDelaySeconds: 60
periodSeconds: 60
timeoutSeconds: 15
name: rabbitmq
ports:
- containerPort: 15672
name: http
protocol: TCP
- containerPort: 5672
name: amqp
protocol: TCP
readinessProbe:
exec:
command:
- rabbitmq-diagnostics
- status
initialDelaySeconds: 20
periodSeconds: 60
timeoutSeconds: 10
volumeMounts:
- mountPath: /etc/rabbitmq
name: config-volume
readOnly: false
- mountPath: /var/lib/rabbitmq
name: rabbitmq-storage
readOnly: false
- name: timezone
mountPath: /etc/localtime
readOnly: true
serviceAccountName: rabbitmq-cluster
terminationGracePeriodSeconds: 30
volumes:
- name: config-volume
configMap:
items:
- key: rabbitmq.conf
path: rabbitmq.conf
- key: enabled_plugins
path: enabled_plugins
name: rabbitmq-cluster-config
- name: timezone
hostPath:
path: /usr/share/zoneinfo/Asia/Shanghai
volumeClaimTemplates:
- metadata:
name: rabbitmq-storage
spec:
accessModes:
- ReadWriteMany
storageClassName: "managed-nfs-storage"
resources:
requests:
storage: 2Gi
3.6 部署检查
➜ rabbitmq-cluster pwd
/Users/ssgeek/Documents/k8s-manifests/rabbitmq-cluster
➜ rabbitmq-cluster ls
01-rabbitmq-configmap.yaml 02-rabbitmq-service.yaml 03-rabbitmq-rbac.yaml 04-rabbitmq-cluster-sts.yaml
➜ rabbitmq-cluster kubectl apply -f .
configmap/rabbitmq-cluster-config created
service/rabbitmq-cluster created
service/rabbitmq-cluster-manage created
serviceaccount/rabbitmq-cluster created
role.rbac.authorization.k8s.io/rabbitmq-cluster created
rolebinding.rbac.authorization.k8s.io/rabbitmq-cluster created
statefulset.apps/rabbitmq-cluster created
等待一段时间,查看创建的相关资源
➜ rabbitmq-cluster kubectl get po,sts -l app=rabbitmq-cluster
NAME READY STATUS RESTARTS AGE
pod/rabbitmq-cluster-0 1/1 Running 0 3m22s
pod/rabbitmq-cluster-1 1/1 Running 0 2m18s
pod/rabbitmq-cluster-2 1/1 Running 0 2m23s
NAME READY AGE
statefulset.apps/rabbitmq-cluster 3/3 3m25s
查看日志,从日志的最后部分观察集群建立的状态
➜ rabbitmq-cluster kubectl logs -f rabbitmq-cluster-0
'/etc/rabbitmq/rabbitmq.conf' -> '/var/lib/rabbitmq/rabbitmq.conf'
2021-02-17 03:30:39.445 [info] <0.9.0> Feature flags: list of feature flags found:
2021-02-17 03:30:39.445 [info] <0.9.0> Feature flags: [ ] drop_unroutable_metric
2021-02-17 03:30:39.445 [info] <0.9.0> Feature flags: [ ] empty_basic_get_metric
2021-02-17 03:30:39.445 [info] <0.9.0> Feature flags: [ ] implicit_default_bindings
2021-02-17 03:30:39.445 [info] <0.9.0> Feature flags: [ ] quorum_queue
2021-02-17 03:30:39.445 [info] <0.9.0> Feature flags: [ ] virtual_host_metadata
2021-02-17 03:30:39.445 [info] <0.9.0> Feature flags: feature flag states written to disk: yes
2021-02-17 03:30:39.544 [info] <0.269.0> ra: meta data store initialised. 0 record(s) recovered
2021-02-17 03:30:39.547 [info] <0.274.0> WAL: recovering []
2021-02-17 03:31:10.676 [info] <0.313.0>
Starting RabbitMQ 3.8.3 on Erlang 22.3.4.1
Copyright (c) 2007-2020 Pivotal Software, Inc.
Licensed under the MPL 1.1. Website: https://rabbitmq.com
## ## RabbitMQ 3.8.3
## ##
########## Copyright (c) 2007-2020 Pivotal Software, Inc.
###### ##
########## Licensed under the MPL 1.1. Website: https://rabbitmq.com
Doc guides: https://rabbitmq.com/documentation.html
Support: https://rabbitmq.com/contact.html
Tutorials: https://rabbitmq.com/getstarted.html
Monitoring: https://rabbitmq.com/monitoring.html
Logs: <stdout>
Config file(s): /var/lib/rabbitmq/rabbitmq.conf
Starting broker...2021-02-17 03:31:10.678 [info] <0.313.0>
node : rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local
home dir : /var/lib/rabbitmq
config file(s) : /var/lib/rabbitmq/rabbitmq.conf
cookie hash : H+IQL2spD4MDV4jPi7mMAg==
log(s) : <stdout>
database dir : /var/lib/rabbitmq/mnesia/rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local
2021-02-17 03:31:10.695 [info] <0.313.0> Running boot step pre_boot defined by app rabbit
...省略中间内容
2021-02-17 03:31:13.273 [info] <0.824.0> Statistics database started.
2021-02-17 03:31:13.273 [info] <0.823.0> Starting worker pool 'management_worker_pool' with 3 processes in it
2021-02-17 03:31:13.467 [info] <0.9.0> Server startup complete; 5 plugins started.
* rabbitmq_peer_discovery_k8s
* rabbitmq_management
* rabbitmq_web_dispatch
* rabbitmq_management_agent
* rabbitmq_peer_discovery_common
completed with 5 plugins.
2021-02-17 03:32:30.060 [info] <0.566.0> node 'rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local' up
2021-02-17 03:32:31.264 [info] <0.566.0> rabbit on node 'rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local' up
2021-02-17 03:33:31.280 [info] <0.566.0> node 'rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local' up
2021-02-17 03:33:32.627 [info] <0.566.0> rabbit on node 'rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local' up
进入到pod
中通过客户端查看集群状态
➜ rabbitmq-cluster kubectl exec -it rabbitmq-cluster-0 bash
root@rabbitmq-cluster-0:/# rabbitmqctl cluster_status
Cluster status of node rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local ...
Basics
Cluster name: rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local
Disk Nodes
rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local
rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local
rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local
Running Nodes
rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local
rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local
rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local
Versions
rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local: RabbitMQ 3.8.3 on Erlang 22.3.4.1
rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local: RabbitMQ 3.8.3 on Erlang 22.3.4.1
rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local: RabbitMQ 3.8.3 on Erlang 22.3.4.1
Alarms
(none)
Network Partitions
(none)
Listeners
Node: rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 25672, protocol: clustering, purpose: inter-node and CLI tool communication
Node: rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 5672, protocol: amqp, purpose: AMQP 0-9-1 and AMQP 1.0
Node: rabbit@rabbitmq-cluster-0.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 15672, protocol: http, purpose: HTTP API
Node: rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 25672, protocol: clustering, purpose: inter-node and CLI tool communication
Node: rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 5672, protocol: amqp, purpose: AMQP 0-9-1 and AMQP 1.0
Node: rabbit@rabbitmq-cluster-1.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 15672, protocol: http, purpose: HTTP API
Node: rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 25672, protocol: clustering, purpose: inter-node and CLI tool communication
Node: rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 5672, protocol: amqp, purpose: AMQP 0-9-1 and AMQP 1.0
Node: rabbit@rabbitmq-cluster-2.rabbitmq-cluster.default.svc.cluster.local, interface: [::], port: 15672, protocol: http, purpose: HTTP API
Feature flags
Flag: drop_unroutable_metric, state: enabled
Flag: empty_basic_get_metric, state: enabled
Flag: implicit_default_bindings, state: enabled
Flag: quorum_queue, state: enabled
Flag: virtual_host_metadata, state: enabled
通过NodePort
访问管理界面
kubectl get svc -l app=rabbitmq-cluster
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
rabbitmq-cluster ClusterIP None <none> 5672/TCP 8m47s
rabbitmq-cluster-manage NodePort 10.1.239.191 <none> 15672:30888/TCP 8m47s
到这里,在k8s
中手动部署一个RabbitMQ
集群就完成啦~
参考:
https://www.rabbitmq.com/cluster-formation.html
https://github.com/rabbitmq/diy-kubernetes-examples