RocketMQ 是一款分布式、队列模型的消息中间件,具有以下特点: 能够保证严格的消息顺序 提供丰富的消息拉取模式 高效的订阅者水平扩展能力 实时的消息订阅机制 亿级消息堆积能力
NameServer:单点,供Producer和Consumer获取Broker地址
Producer:产生并发送消息
Consumer:接受并消费消息
Broker:消息暂存,消息转发
Name Server是RocketMQ的寻址服务。用于把Broker的路由信息做聚合。客户端依靠Name Server决定去获取对应topic的路由信息,从而决定对哪些Broker做连接。
Name Server是一个几乎无状态的结点,Name Server之间采取share-nothing的设计,互不通信。
对于一个Name Server集群列表,客户端连接Name Server的时候,只会选择随机连接一个结点,以做到负载均衡。
Name Server所有状态都从Broker上报而来,本身不存储任何状态,所有数据均在内存。
如果中途所有Name Server全都挂了,影响到路由信息的更新,不会影响和Broker的通信。
Broker是处理消息存储,转发等处理的服务器。
Broker以group分开,每个group只允许一个master,若干个slave。
只有master才能进行写入操作,slave不允许。
slave从master中同步数据。同步策略取决于master的配置,可以采用同步双写,异步复制两种。
客户端消费可以从master和slave消费。在默认情况下,消费者都从master消费,在master挂后,客户端由于从Name Server中感知到Broker挂机,就会从slave消费。
Broker向所有的NameServer结点建立长连接,注册Topic信息。
1.强调集群无单点,可扩展
2.任意一点高可用,水平可扩展
3.海量消息堆积能力,消息堆积后,写入低延迟。
4.支持上万个队列
5.消息失败重试机制
6.消息可查询
7.开源社区活跃
8.成熟度(经过双十一考验)
192.168.110.187 nameServer1,brokerServer1
192.168.110.188 nameServer2,brokerServer2
vi /etc/hosts
192.168.110.187 rocketmq-nameserver1
192.168.110.187 rocketmq-master1
192.168.110.188 rocketmq-nameserver2
192.168.110.188 rocketmq-master2
service network restart
注意: Error:No suitable device found: no device found for connection "System eth0"
解决办法:
(1)ifconfig -a 查看物理 MAC HWADDR 的值
(2)vim 编辑文件 /etc/sysconfig/network-scripts/ifcfg-eth0中修改ifconfig中查出的MAC HWADDR值;
# 上传alibaba-rocketmq-3.2.6.tar.gz文件至/usr/local
# tar -zxvf alibaba-rocketmq-3.2.6.tar.gz -C /usr/local
# mv alibaba-rocketmq alibaba-rocketmq-3.2.6
# ln -s alibaba-rocketmq-3.2.6 rocketmq
mkdir /usr/local/rocketmq/store
# mkdir /usr/local/rocketmq/store/commitlog
# mkdir /usr/local/rocketmq/store/consumequeue
# mkdir /usr/local/rocketmq/store/index
# vim /usr/local/rocketmq/conf/2m-noslave/broker-a.properties
# vim /usr/local/rocketmq/conf/2m-noslave/broker-b.properties
# mkdir -p /usr/local/rocketmq/logs
# cd /usr/local/rocketmq/conf && sed -i 's#${user.home}#/usr/local/rocketmq#g' *.xml
vim /usr/local/rocketmq/bin/runbroker.sh
JAVA_OPT="${JAVA_OPT} -server -Xms1g -Xmx1g -Xmn512m -
XX:PermSize=128m -XX:MaxPermSize=320m"
vim /usr/local/rocketmq/bin/runserver.sh
JAVA_OPT="${JAVA_OPT} -server -Xms1g -Xmx1g -Xmn512m -
XX:PermSize=128m -XX:MaxPermSize=320m"
# cd /usr/local/rocketmq/bin
# nohup sh mqnamesrv &
cd /usr/local/rocketmq/bin
# nohup sh mqbroker -c /usr/local/rocketmq/conf/2m-noslave/broker-a.properties >/dev/null 2>&1 &
# netstat -ntlp
# jps
# tail -f -n 500 /usr/local/rocketmq/logs/rocketmqlogs/broker.log
# tail -f -n 500 /usr/local/rocketmq/logs/rocketmqlogs/namesrv.log
cd /usr/local/rocketmq/bin
# nohup sh mqbroker -c /usr/local/rocketmq/conf/2m-noslave/broker-b.properties >/dev/null 2>&1 &
# netstat -ntlp
# jps
# tail -f -n 500 /usr/local/rocketmq/logs/rocketmqlogs/broker.log
# tail -f -n 500 /usr/local/rocketmq/logs/rocketmqlogs/namesrv.log
将rocketmq-web-console 部署到webapps目录中。
/usr/local/apache-tomcat-7.0.65/webapps/rocketmq-web-console/WEB-INF/classes/
修改config.properties
rocketmq.namesrv.addr=192.168.110.195:9876;192.168.110.199:9876
vi /etc/profile
export JAVA_HOME=/usr/local/jdk1.7.0_80
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export PATH=$JAVA_HOME/bin:$PATH
source /etc/profile
com.alibaba.rocketmq
rocketmq-client
3.0.10
com.alibaba.rocketmq
rocketmq-all
3.0.10
pom
ch.qos.logback
logback-classic
1.1.1
ch.qos.logback
logback-core
1.1.1
junit
junit
4.10
test
public class Producer {
public static void main(String[] args) throws MQClientException {
DefaultMQProducer producer = new DefaultMQProducer("rmq-group");
producer.setNamesrvAddr("192.168.110.195:9876;192.168.110.199:9876");
producer.setInstanceName("producer");
producer.start();
try {
for (int i = 0; i < 10; i++) {
Thread.sleep(1000); // 每秒发送一次MQ
Message msg = new Message("itmayiedu-topic", // topic 主题名称
"TagA", // tag 临时值
("itmayiedu-"+i).getBytes()// body 内容
);
SendResult sendResult = producer.send(msg);
System.out.println(sendResult.toString());
}
} catch (Exception e) {
e.printStackTrace();
}
producer.shutdown();
}
}
public class Consumer {
public static void main(String[] args) throws MQClientException {
DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("rmq-group");
consumer.setNamesrvAddr("192.168.110.195:9876;192.168.110.199:9876");
consumer.setInstanceName("consumer");
consumer.subscribe("itmayiedu-topic", "TagA");
consumer.registerMessageListener(new MessageListenerConcurrently() {
@Override
public ConsumeConcurrentlyStatus consumeMessage(List
msgs, ConsumeConcurrentlyContext context) { for (MessageExt msg : msgs) {
System.out.println(msg.getMsgId()+"---"+new String(msg.getBody()));
}
return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
}
});
consumer.start();
System.out.println("Consumer Started.");
}
}
MQ 消费者的消费逻辑失败时,可以通过设置返回状态达到消息重试的结果。
MQ 消息重试只针对集群消费方式生效;广播方式不提供失败重试特性,即消费失败后,失败消息不再重试,继续消费新的消息。
public class Consumer {
public static void main(String[] args) throws MQClientException {
DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("rmq-group");
consumer.setNamesrvAddr("192.168.110.195:9876;192.168.110.199:9876");
consumer.setInstanceName("consumer");
consumer.subscribe("itmayiedu-topic", "TagA");
consumer.registerMessageListener(new MessageListenerConcurrently() {
@Override
public ConsumeConcurrentlyStatus consumeMessage(List
msgs, ConsumeConcurrentlyContext context) { for (MessageExt msg : msgs) {
System.out.println(msg.getMsgId() + "---" + new String(msg.getBody()));
}
try {
int i = 1 / 0;
} catch (Exception e) {
e.printStackTrace();
// 需要重试
return ConsumeConcurrentlyStatus.RECONSUME_LATER;
}
// 不需要重试
return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
}
});
consumer.start();
System.out.println("Consumer Started.");
}
}
注意:每次重试后,消息ID都不一致,所以不能使用消息ID判断幂等。
注意:每次重试后,消息ID都不一致,所以不能使用消息ID判断幂等。
解决办法:使用自定义全局ID判断幂等,例如流水ID、订单号
使用msg.setKeys 进行区分
public class Producer {
public static void main(String[] args) throws MQClientException {
DefaultMQProducer producer = new DefaultMQProducer("rmq-group");
producer.setNamesrvAddr("192.168.110.195:9876;192.168.110.199:9876");
producer.setInstanceName("producer");
producer.start();
try {
for (int i = 0; i < 1; i++) {
Thread.sleep(1000); // 每秒发送一次MQ
Message msg = new Message("itmayiedu-topic", // topic 主题名称
"TagA", // tag 临时值
("itmayiedu-6" + i).getBytes()// body 内容
);
msg.setKeys(System.currentTimeMillis() + "");
SendResult sendResult = producer.send(msg);
System.out.println(sendResult.toString());
}
} catch (Exception e) {
e.printStackTrace();
}
producer.shutdown();
}
}
static private Map
logMap = new HashMap<>();
public static void main(String[] args) throws MQClientException {
DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("rmq-group");
consumer.setNamesrvAddr("192.168.110.195:9876;192.168.110.199:9876");
consumer.setInstanceName("consumer");
consumer.subscribe("itmayiedu-topic", "TagA");
consumer.registerMessageListener(new MessageListenerConcurrently() {
@Override
public ConsumeConcurrentlyStatus consumeMessage(List
msgs, ConsumeConcurrentlyContext context) { String key = null;
String msgId = null;
try {
for (MessageExt msg : msgs) {
key = msg.getKeys();
if (logMap.containsKey(key)) {
// 无需继续重试。
System.out.println("key:"+key+",无需重试...");
return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
}
msgId = msg.getMsgId();
System.out.println("key:" + key + ",msgid:" + msgId + "---" + new String(msg.getBody()));
int i = 1 / 0;
}
} catch (Exception e) {
e.printStackTrace();
return ConsumeConcurrentlyStatus.RECONSUME_LATER;
} finally {
logMap.put(key, msgId);
}
return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
}
});
consumer.start();
System.out.println("Consumer Started.");
}
https://help.aliyun.com/document_detail/44397.html?spm=a2c4g.11186623.6.577.sPsbuu