为什么activemq自己打开套接字

Question

我遇到了这种情况，其中我试图运行使用 SSL 的 activemq，但我看到了 SSL 异常。

这是我的 activemq.xml.

的除外

<transportConnectors>
    <transportConnector name="openwire" uri="tcp://0.0.0.0:${JMS_PORT}" />
    <transportConnector name="stomp" uri="stomp://0.0.0.0:${JMS_STOMP_PORT}"/>
    <transportConnector name="ssl" uri="ssl://0.0.0.0:${JMS_SSL_PORT}"/>
</transportConnectors>

<sslContext>
    <sslContext
        keyStore="file:${JMS_KEY_STORE}"
        keyStorePassword="${JMS_KEY_STORE_PASSWORD}"
        trustStore="file:${JMS_TRUST_STORE}"
        trustStorePassword="${JMS_TRUST_STORE_PASSWORD}"
    />
</sslContext>

<networkConnectors>
    <networkConnector 
        name="host1 and host2" 
        uri="static://(${JMS_X_SITE_CSV_URL})?wireFormat=ssl&amp;wireFormat.maxInactivityDuration=30000"
        dynamicOnly="true"
        suppressDuplicateQueueSubscriptions = "true"
        networkTTL="1"
    />
</networkConnectors>

变量的值如下。

JMS_PORT=10029
JMS_STOMP_PORT=10030
JMS_SSL_PORT=10031
JMS_X_SITE_CSV_URL=tcp://localhost:10031/

现在，通过上述配置，我看到 javax.net.ssl.SSLException 的错误如下：

2016-09-20 14:47:48,619 | ERROR | Could not accept connection from tcp://localhost:54869: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? | org.apache.activemq.broker.TransportConnector | ActiveMQ BrokerService[divinedragonbox] Task-3
2016-09-20 14:47:49,628 | ERROR | Could not accept connection from tcp://localhost:54871: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? | org.apache.activemq.broker.TransportConnector | ActiveMQ BrokerService[divinedragonbox] Task-9
2016-09-20 14:47:51,639 | ERROR | Could not accept connection from tcp://localhost:54893: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? | org.apache.activemq.broker.TransportConnector | ActiveMQ BrokerService[divinedragonbox] Task-12
2016-09-20 14:47:55,645 | ERROR | Could not accept connection from tcp://localhost:54902: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? | org.apache.activemq.broker.TransportConnector | ActiveMQ BrokerService[divinedragonbox] Task-20
2016-09-20 14:48:03,653 | ERROR | Could not accept connection from tcp://localhost:54906: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? | org.apache.activemq.broker.TransportConnector | ActiveMQ BrokerService[divinedragonbox] Task-31
2016-09-20 14:48:19,661 | ERROR | Could not accept connection from tcp://localhost:54915: javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection? | org.apache.activemq.broker.TransportConnector | ActiveMQ BrokerService[divinedragonbox] Task-50

错误消息起初看起来很神秘，但后来就明白了。当我实际尝试连接到 SSL 端口 -10031 时，我使用 tcp:// 配置了网络连接器。此问题导致套接字保留在 CLOSE_WAIT 中，从而为 ActiveMQ 本身使用了大量内存。

下面是悬空套接字在出现问题时的样子。

tcp6       0      0 127.0.0.1:54869      127.0.0.1:10031       CLOSE_WAIT  4807/java           
tcp6       0      0 127.0.0.1:54871      127.0.0.1:10031       CLOSE_WAIT  4807/java           
tcp6       1      0 127.0.0.1:54893      127.0.0.1:10031       CLOSE_WAIT  4807/java           
tcp6       0      0 127.0.0.1:54902      127.0.0.1:10031       CLOSE_WAIT  4807/java           
tcp6       1      0 127.0.0.1:54915      127.0.0.1:10031       CLOSE_WAIT  4807/java           
tcp6       1      0 127.0.0.1:54922      127.0.0.1:10031       CLOSE_WAIT  4807/java

So, I fixed the JMS_X_SITE_CSV_URL to ssl://localhost:10031/ and the issue was resolved.

现在，这是我的问题（很抱歉来到这里的冗长解释）。

Why was activemq opening sockets with itself?

我在解决这个问题时在想，套接字被 producers/consumers 打开，同时试图 read/write 数据离开队列，但是当我只是运行ning activemq 进程（没有其他 java 进程）以隔离它正在打开与自身的连接。

Answer 1

0.0.0.0表示activemq会监听所有可用的接口，包括127.0.0.1。有关详细信息，请参阅 What is the difference between 0.0.0.0, 127.0.0.1 and localhost?

Answer 2

由于配置块，ActiveMQ 正在尝试连接到它自己的代理 - networkConnector。

To provide massive scalability of a large messaging fabric you typically want to allow many brokers to be connected together into a network so that you can have as many clients as you wish all logically connected together - and running as many message brokers as you need based on your number of clients and network topology.

http://activemq.apache.org/networks-of-brokers.html

因为，我已经将 JMS_X_SITE_CSV_URL 配置为本地主机，activemq 正在尝试连接到它自己的代理。

关于此的更多详细信息 -

为什么activemq自己打开套接字

Why does activemq opening sockets with itself

java

networking

activemq

message-queue