內容目錄
1. RocketMQ是什么？
2. 下載並解壓
3. 啟動NameServer
4. 啟動 Broker
5. 關閉消息隊列
1. RocketMQ是什么？
RocketMQ是一種消息隊列。何為消息隊列？即數據結構中一種“先進先出”的數據結構。在微服務中，分布式消息隊列可以解決什么問題？應用解耦、流量削峰、消息分發、保證最終一致性、方便動態擴容等。
RocketMQ中不可不知的四個角色：Producer（消息生產者）、Consumer（消息消費者）、Broker（消息暫存者）、NameServer（消息協調者）。由這四個角色的作用可知，啟動 RocketMQ 時，應該先啟動 NameServer，然后再啟動 Broker，后續需要發送消息就用 Producer，需要接收消息就用 Consumer。
2. 下載並解壓
cd /usr/local wget -c http://mirrors.shu.edu.cn/apache/rocketmq/4.3.2/rocketmq-all-4.3.2-bin-release.zip unzip rocketmq-all-4.3.2-bin-release.zip -d . cd rocketmq-all-4.3.2-bin-release ls [root@153-215 rocketmq-all-4.3.2-bin-release]# ls benchmark bin conf lib LICENSE NOTICE README.md
3. 啟動NameServer
啟動NameServer：nohup sh bin/mqnamesrv &，然而發現不能正常啟動，如下：
[root@153-215 rocketmq-all-4.3.2-bin-release]# nohup sh bin/mqnamesrv & [1] 32673 [root@153-215 rocketmq-all-4.3.2-bin-release]# nohup: ignoring input and appending output to ‘nohup.out’ [1]+ Exit 1 nohup sh bin/mqnamesrv
查看nohup.out：
[root@153-215 rocketmq-all-4.3.2-bin-release]# cat nohup.out ERROR: Please set the JAVA_HOME variable in your environment, We need java(x64)! !!
可是，本機明明已經安裝jdk並且已經配置了 JAVA_HOME 環境變量呀：
[root@153-215 rocketmq-all-4.3.2-bin-release]# java -version java version "1.8.0_171" Java(TM) SE Runtime Environment (build 1.8.0_171-b11) Java HotSpot(TM) 64-Bit Server VM (build 25.171-b11, mixed mode)
環境變量設置：
#####################java env############### JAVA_HOME=/opt/jdk1.8.0_171 CLASSPATH=.:$JAVA_HOME/lib/tools.jar:$JAVA_HOME/lib/dt.jar PATH=$JAVA_HOME/bin:$HOME/bin:$HOME/.local/bin:$PATH
查看 runserver.sh 腳本，發現有這么三行命令：
[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=$HOME/jdk/java [ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=/usr/java [ ! -e "$JAVA_HOME/bin/java" ] && error_exit "Please set the JAVA_HOME variable in your environment, We need java(x64)!"
將其注釋之，繼續往下看，發現下面兩行：
export JAVA_HOME export JAVA="$JAVA_HOME/bin/java"
嗯，果斷修改 JAVA_HOME 的值如下：
export JAVA_HOME=/opt/jdk1.8.0_171
再次啟動 NameServer ：
[root@157-89 rocketmq-all-4.3.2-bin-release]# nohup sh bin/mqnamesrv & [1] 31098 [root@157-89 rocketmq-all-4.3.2-bin-release]# nohup: ignoring input and appending output to ‘nohup.out’ [root@157-89 rocketmq-all-4.3.2-bin-release]# ls benchmark bin conf lib LICENSE nohup.out NOTICE README.md [root@157-89 rocketmq-all-4.3.2-bin-release]# cat nohup.out Java HotSpot(TM) 64-Bit Server VM warning: Using the DefNew young collector with the CMS collector is deprecated and will likely be removed in a future release Java HotSpot(TM) 64-Bit Server VM warning: UseCMSCompactAtFullCollection is deprecated and will likely be removed in a future release. The Name Server boot success. serializeType=JSON
此處可以看到 NameServer 已成功啟動，查看 NameServer 日志：
[root@157-89 rocketmq-all-4.3.2-bin-release]# tail -f ~/logs/rocketmqlogs/namesrv.log 2019-01-07 20:19:36 INFO main - tls.client.certPath = null 2019-01-07 20:19:36 INFO main - tls.client.authServer = false 2019-01-07 20:19:36 INFO main - tls.client.trustCertPath = null 2019-01-07 20:19:36 INFO main - Using OpenSSL provider 2019-01-07 20:19:37 INFO main - SSLContext created for server 2019-01-07 20:19:37 INFO NettyEventExecutor - NettyEventExecutor service started 2019-01-07 20:19:37 INFO FileWatchService - FileWatchService service started 2019-01-07 20:19:37 INFO main - The Name Server boot success. serializeType=JSON 2019-01-07 20:20:37 INFO NSScheduledThread1 - -------------------------------------------------------- 2019-01-07 20:20:37 INFO NSScheduledThread1 - configTable SIZE: 0
NameServer 啟動成功
4. 啟動 Broker
啟動Broker：nohup sh bin/mqbroker -n localhost:9876&，然而發現不能正常啟動，如下：
[root@153-215 rocketmq-all-4.3.2-bin-release]# nohup sh bin/mqbroker -n localhost:9876& [1] 28571 [root@153-215 rocketmq-all-4.3.2-bin-release]# nohup: ignoring input and appending output to ‘nohup.out’ [1]+ Exit 1 nohup sh bin/mqbroker -n localhost:9876
查看nohup.out，發現里面多了這么幾行錯誤信息：
Java HotSpot(TM) 64-Bit Server VM warning: INFO: os::commit_memory(0x00000005c0000000, 8589934592, 0) failed; error='Cannot allocate memory' (errno=12) # # There is insufficient memory for the Java Runtime Environment to continue. # Native memory allocation (mmap) failed to map 8589934592 bytes for committing reserved memory. # An error report file with more information is saved as: # /usr/local/rocketmq-all-4.3.2-bin-release/hs_err_pid28580.log
遂，查看 hs_err_pid28580.log：
[root@153-215 rocketmq-all-4.3.2-bin-release]# tail -1000f /usr/local/rocketmq-all-4.3.2-bin-release/hs_err_pid28580.log # # There is insufficient memory for the Java Runtime Environment to continue. # Native memory allocation (mmap) failed to map 8589934592 bytes for committing reserved memory. # Possible reasons: # The system is out of physical RAM or swap space # In 32 bit mode, the process size limit was hit # Possible solutions: # Reduce memory load on the system # Increase physical memory or swap space # Check if swap backing store is full # Use 64 bit Java on a 64 bit OS # Decrease Java heap size (-Xmx/-Xms) # Decrease number of Java threads # Decrease Java thread stack sizes (-Xss) # Set larger code cache with -XX:ReservedCodeCacheSize= # This output file may be truncated or incomplete. # # Out of Memory Error (os_linux.cpp:2640), pid=28580, tid=0x00007fbc93a6c700 # # JRE version: (8.0_171-b11) (build ) # Java VM: Java HotSpot(TM) 64-Bit Server VM (25.171-b11 mixed mode linux-amd64 compressed oops) # Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again ........ VM Arguments: jvm_args: -Xms8g -Xmx8g -Xmn4g -XX:+UseG1GC -XX:G1HeapRegionSize=16m -XX:G1ReservePercent=25 -XX:InitiatingHeapOccupancyPercent=30 -XX:SoftRefLRUPolicyMSPerMB=0 -XX:SurvivorRatio=8 -verbose:gc -Xloggc:/dev/shm/mq_gc_%p.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+PrintGCApplicationStoppedTime -XX:+PrintAdaptiveSizePolicy -XX:+UseGCLogFileRotation -XX:NumberOfGCLogFiles=5 -XX:GCLogFileSize=30m -XX:-OmitStackTraceInFastThrow -XX:+AlwaysPreTouch -XX:MaxDirectMemorySize=15g -XX:-UseLargePages -XX:-UseBiasedLocking -Djava.ext.dirs=/opt/jdk1.8.0_171/jre/lib/ext:/usr/local/rocketmq-all-4.3.2-bin-release/bin/../lib java_command: org.apache.rocketmq.broker.BrokerStartup -n localhost:9876 java_class_path (initial): .:/usr/local/rocketmq-all-4.3.2-bin-release/bin/../conf:.:/opt/jdk1.8.0_171/lib/tools.jar:/opt/jdk1.8.0_171/lib/dt.jar Launcher Type: SUN_STANDARD ......
大概意思呢，就是說，啟動broker時內存不足，為什么內存不足呢？因為啟動時候指定了JVM最大可用內存和最小可用內存均為8G，年輕代大小為2G。
查看Broker啟動腳本，發現果然指定了這三個jvm啟動參數，然后意外發現對於JAVA_HOME的設置，runbroker.sh與runserver.sh是一樣一樣的：
[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=$HOME/jdk/java [ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=/usr/java [ ! -e "$JAVA_HOME/bin/java" ] && error_exit "Please set the JAVA_HOME variable in your environment, We need java(x64)!" export JAVA_HOME export JAVA="$JAVA_HOME/bin/java" export BASE_DIR=$(dirname $0)/.. export CLASSPATH=.:${BASE_DIR}/conf:${CLASSPATH} #=========================================================================================== # JVM Configuration #=========================================================================================== JAVA_OPT="${JAVA_OPT} -server -Xms8g -Xmx8g -Xmn4g"
遂，修改啟動腳本中JAVA_HOME的設置以及JVM啟動腳本如下：
#[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=$HOME/jdk/java #[ ! -e "$JAVA_HOME/bin/java" ] && JAVA_HOME=/usr/java #[ ! -e "$JAVA_HOME/bin/java" ] && error_exit "Please set the JAVA_HOME variable in your environment, We need java(x64)!" export JAVA_HOME=/opt/jdk1.8.0_171 export JAVA="$JAVA_HOME/bin/java" export BASE_DIR=$(dirname $0)/.. export CLASSPATH=.:${BASE_DIR}/conf:${CLASSPATH} #=========================================================================================== # JVM Configuration #=========================================================================================== JAVA_OPT="${JAVA_OPT} -server -Xms256m -Xmx256m -Xmn128m"
再次啟動Broker：
[root@153-215 rocketmq-all-4.3.2-bin-release]# nohup sh bin/mqbroker -n localhost:9876& [1] 29092 [root@153-215 rocketmq-all-4.3.2-bin-release]# nohup: ignoring input and appending output to ‘nohup.out’ [root@153-215 rocketmq-all-4.3.2-bin-release]# cat nohup.out Java HotSpot(TM) 64-Bit Server VM warning: INFO: os::commit_memory(0x00000005c0000000, 8589934592, 0) failed; error='Cannot allocate memory' (errno=12) # # There is insufficient memory for the Java Runtime Environment to continue. # Native memory allocation (mmap) failed to map 8589934592 bytes for committing reserved memory. # An error report file with more information is saved as: # /usr/local/rocketmq-all-4.3.2-bin-release/hs_err_pid28580.log The broker[153-215, 39.107.153.215:10911] boot success. serializeType=JSON and name server is localhost:9876
此處可以看到Broker已啟動成功，查看Broker日志：
[root@157-89 rocketmq-all-4.3.2-bin-release]# tail -1000f ~/logs/rocketmqlogs/broker.log 2019-01-09 16:13:08 INFO main - rocketmqHome=/usr/local/rocketmq-all-4.3.2-bin-release 2019-01-09 16:13:08 INFO main - namesrvAddr=localhost:9876 ...... 2019-01-09 16:13:09 INFO FileWatchService - FileWatchService service started 2019-01-09 16:13:09 INFO PullRequestHoldService - PullRequestHoldService service started 2019-01-09 16:13:09 INFO brokerOutApi_thread_1 - register broker to name server localhost:9876 OK 2019-01-09 16:13:09 INFO main - Start transaction service! 2019-01-09 16:13:09 INFO main - The broker[157-89, 39.107.157.89:10911] boot success. serializeType=JSON and name server is localhost:9876
5. 關閉消息隊列
關閉 Broker：
[root@153-215 rocketmq-all-4.3.2-bin-release]# sh bin/mqshutdown broker The mqbroker(29099) is running... Send shutdown request to mqbroker(29099) OK
關閉 NameServer：
[root@153-215 rocketmq-all-4.3.2-bin-release]# sh bin/mqshutdown namesrv The mqnamesrv(14283) is running... Send shutdown request to mqnamesrv(14283) OK