ActiveMQ Artemis CLI工具提示端口9876被占用问题咨询

问题描述 #

我运行的是ActiveMQ Artemis 2.14.0，今天使用Broker的bin目录下的CLI工具时，哪怕执行help命令都会提示端口9876被占用。检查后发现这个端口正是运行Artemis的用户在占用，同时Broker的lock目录下有个空的cli.lock文件。现在我想给Broker添加新用户，想问下是不是必须关闭Broker才能操作，或者有没有其他方式正常使用CLI？

报错信息 #

WARNING: Failed to instantiate LoggerFinder provider; Using default.
Error: Exception thrown by the agent : java.rmi.server.ExportException: Port already in use: 9876; nested exception is:
        java.net.BindException: Address already in use (Bind failed)
jdk.internal.agent.AgentConfigurationError: java.rmi.server.ExportException: Port already in use: 9876; nested exception is:
        java.net.BindException: Address already in use (Bind failed)
        at jdk.management.agent/sun.management.jmxremote.ConnectorBootstrap.startRemoteConnectorServer(ConnectorBootstrap.java:491)
        at jdk.management.agent/jdk.internal.agent.Agent.startAgent(Agent.java:447)
        at jdk.management.agent/jdk.internal.agent.Agent.startAgent(Agent.java:599)
Caused by: java.rmi.server.ExportException: Port already in use: 9876; nested exception is:
        java.net.BindException: Address already in use (Bind failed)
        at java.rmi/sun.rmi.transport.tcp.TCPTransport.listen(TCPTransport.java:335)
        at java.rmi/sun.rmi.transport.tcp.TCPTransport.exportObject(TCPTransport.java:243)
        at java.rmi/sun.rmi.transport.tcp.TCPEndpoint.exportObject(TCPEndpoint.java:412)
        at java.rmi/sun.rmi.transport.LiveRef.exportObject(LiveRef.java:147)
        at java.rmi/sun.rmi.server.UnicastServerRef.exportObject(UnicastServerRef.java:234)
        at java.rmi/sun.rmi.registry.RegistryImpl.setup(RegistryImpl.java:220)
        at java.rmi/sun.rmi.registry.RegistryImpl.<init>(RegistryImpl.java:180)
        at jdk.management.agent/sun.management.jmxremote.SingleEntryRegistry.<init>(SingleEntryRegistry.java:49)
        at jdk.management.agent/sun.management.jmxremote.ConnectorBootstrap.exportMBeanServer(ConnectorBootstrap.java:836)
        at jdk.management.agent/sun.management.jmxremote.ConnectorBootstrap.startRemoteConnectorServer(ConnectorBootstrap.java:479)
        ... 2 more
Caused by: java.net.BindException: Address already in use (Bind failed)
        at java.base/java.net.PlainSocketImpl.socketBind(Native Method)
        at java.base/java.net.AbstractPlainSocketImpl.bind(AbstractPlainSocketImpl.java:452)
        at java.base/java.net.ServerSocket.bind(ServerSocket.java:395)
        at java.base/java.net.ServerSocket.<init>(ServerSocket.java:257)
        at java.base/java.net.ServerSocket.<init>(ServerSocket.java:149)
        at java.rmi/sun.rmi.transport.tcp.TCPDirectSocketFactory.createServerSocket(TCPDirectSocketFactory.java:45)
        at java.rmi/sun.rmi.transport.tcp.TCPEndpoint.newServerSocket(TCPEndpoint.java:670)
        at java.rmi/sun.rmi.transport.tcp.TCPTransport.listen(TCPTransport.java:324)
        ... 11 more

etc/artemis.profile配置 #

# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

ARTEMIS_HOME='/opt/artemis-2.14.0'
ARTEMIS_INSTANCE='/var/lib/broker-HA'
ARTEMIS_DATA_DIR='/var/lib/broker-HA/data'
ARTEMIS_ETC_DIR='/var/lib/broker-HA/etc'
ARTEMIS_OOME_DUMP='/var/lib/broker-HA/log/oom_dump.hprof'

# The logging config will need an URI
# this will be encoded in case you use spaces or special characters
# on your directory structure
ARTEMIS_INSTANCE_URI='file:/var/lib/broker-HA/'
ARTEMIS_INSTANCE_ETC_URI='file:/var/lib/broker-HA/etc/'

# Cluster Properties: Used to pass arguments to ActiveMQ Artemis which can be referenced in broker.xml
#ARTEMIS_CLUSTER_PROPS="-Dactivemq.remoting.default.port=61617 -Dactivemq.remoting.amqp.port=5673 -Dactivemq.remoting.stomp.port=61614 -Dactivemq.remoting.hornetq.port=5446"


# Java Opts
if [ -z "$JAVA_ARGS" ]; then
    JAVA_ARGS=" -Dcom.sun.management.jmxremote=true -Dcom.sun.management.jmxremote.port=9876 -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false -Djava.rmi.server.hostname=[ip] -XX:+PrintClassHistogram -XX:+UseG1GC -XX:+UseStringDeduplication -Xms512M -Xmx2G -Dhawtio.realm=activemq  -Dhawtio.offline=true -Dhawtio.role=amq -Dhawtio.rolePrincipalClasses=org.apache.activemq.artemis.spi.core.security.jaas.RolePrincipal -Djolokia.policyLocation=${ARTEMIS_INSTANCE_ETC_URI}jolokia-access.xml"
fi

#
# Logs Safepoints JVM pauses: Uncomment to enable them
# In addition to the traditional GC logs you could enable some JVM flags to know any meaningful and "hidden" pause that could
# affect the latencies of the services delivered by the broker, including those that are not reported by the classic GC logs
# and dependent by JVM background work (eg method deoptimizations, lock unbiasing, JNI, counted loops and obviously GC activity).
# Replace "all_pauses.log" with the file name you want to log to.
# JAVA_ARGS="$JAVA_ARGS -XX:+PrintSafepointStatistics -XX:PrintSafepointStatisticsCount=1 -XX:+PrintGCApplicationStoppedTime -XX:+PrintGCApplicationConcurrentTime -XX:+LogVMOutput -XX:LogFile=all_pauses.log"

#
# Enables the dumping of the java heap when a java.lang.OutOfMemoryError exception is thrown.
# JAVA_ARGS="$JAVA_ARGS -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=${ARTEMIS_OOME_DUMP}"

# Debug args: Uncomment to enable debug
#DEBUG_ARGS="-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=5005"

# Debug args: Uncomment for async profiler
#DEBUG_ARGS="-XX:+UnlockDiagnosticVMOptions -XX:+DebugNonSafepoints"

解决方案 #

核心原因 #

端口9876被占用是因为你在artemis.profile里配置了Broker的JMX远程监听端口为9876，而CLI工具默认会尝试启动一个本地JMX服务并绑定到这个端口，和正在运行的Broker的JMX端口冲突。另外空的cli.lock文件是之前CLI进程异常退出留下的，也会阻碍新的CLI进程启动。

无需关闭Broker的操作步骤 #

1. 清理异常锁文件
   先删除lock目录下的cli.lock文件，解除锁限制：

rm /var/lib/broker-HA/lock/cli.lock

2. 直接连接Broker的JMX服务
   既然Broker已经在监听9876端口的JMX服务，让CLI复用这个连接即可，执行添加用户命令时加上--url参数：

./artemis user add --url service:jmx:rmi:///jndi/rmi://[你的BrokerIP]:9876/jmxrmi

把[你的BrokerIP]替换成artemis.profile里java.rmi.server.hostname配置的IP地址。

3. 持久化CLI默认连接（可选）
   如果不想每次都加--url参数，可以修改etc/artemis.profile或者新建etc/artemis-cli.profile，添加以下配置：

ARTEMIS_CLI_ARGS="--url service:jmx:rmi:///jndi/rmi://[你的BrokerIP]:9876/jmxrmi"

之后执行CLI命令就会自动连接到运行中的Broker。

备选方案：关闭Broker操作 #

如果允许Broker停机，直接停止Broker后执行./artemis user add，修改后的用户配置会在Broker重启后生效。

注意事项 #

你当前的JMX配置没有启用认证（-Dcom.sun.management.jmxremote.authenticate=false），生产环境建议开启JMX认证，避免安全风险。

内容的提问来源于stack exchange，提问作者BenW