在使用Zabbix監測Tomcat的運行狀態時，發現在Zabbix Server出現java.rmi.ConnectException: Connection refused to host: 127.0.0.1的錯誤。
網絡上有很多是說/etc/hosts的 但是明顯是針對於zabbix server和tomcat在一臺機器上的問題的解決辦法。
環境：
zabbix server 192.168.2.67
tomcat server（zabbix agent） 182.168.2.62
在zabbix_java.log中看到錯誤：
WARN com.zabbix.gateway.SocketProcessor - error processing request
com.zabbix.gateway.ZabbixException: java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is:
java.net.ConnectException: Connection refused
at com.zabbix.gateway.JMXItemChecker.getValues(JMXItemChecker.java:97) ~[zabbix-java-gateway-3.0.7.jar:na]
at com.zabbix.gateway.SocketProcessor.run(SocketProcessor.java:62) ~[zabbix-java-gateway-3.0.7.jar:na]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) [na:1.7.0_45]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) [na:1.7.0_45]
at java.lang.Thread.run(Thread.java:744) [na:1.7.0_45]
Caused by: java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is:
java.net.ConnectException: Connection refused
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:619) ~[na:1.7.0_45]
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:216) ~[na:1.7.0_45]
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:202) ~[na:1.7.0_45]
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:129) ~[na:1.7.0_45]
at javax.management.remote.rmi.RMIServerImpl_Stub.newClient(Unknown Source) ~[na:1.7.0_45]
at javax.management.remote.rmi.RMIConnector.getConnection(RMIConnector.java:2392) ~[na:1.7.0_45]
at javax.management.remote.rmi.RMIConnector.connect(RMIConnector.java:308) ~[na:1.7.0_45]
at javax.management.remote.JMXConnectorFactory.connect(JMXConnectorFactory.java:268) ~[na:1.7.0_45]
at com.zabbix.gateway.ZabbixJMXConnectorFactory$1.run(ZabbixJMXConnectorFactory.java:76) ~[zabbix-java-gateway-3.0.7.jar:na]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) ~[na:1.7.0_45]
at java.util.concurrent.FutureTask.run(FutureTask.java:262) ~[na:1.7.0_45]
... 3 common frames omitted
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:1.7.0_45]
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339) ~[na:1.7.0_45]
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200) ~[na:1.7.0_45]
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182) ~[na:1.7.0_45]
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.7.0_45]
at java.net.Socket.connect(Socket.java:579) ~[na:1.7.0_45]
at java.net.Socket.connect(Socket.java:528) ~[na:1.7.0_45]
at java.net.Socket.<init>(Socket.java:425) ~[na:1.7.0_45]
at java.net.Socket.<init>(Socket.java:208) ~[na:1.7.0_45]
at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:40) ~[na:1.7.0_45]
at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:147) ~[na:1.7.0_45]
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:613) ~[na:1.7.0_45]
... 13 common frames omitted
接下來用cmdline-jmxclient-0.10.3.jar檢查下是否能夠調取tomcat服務器的監控數據。
java -jar cmdline-jmxclient-0.10.3.jar - 192.168.2.62:12345 java.lang:type=Memory NonHeapMemoryUsage
Exception in thread "main" java.rmi.ConnectException: Connection refused to host: 127.0.0.1; nested exception is:
java.net.ConnectException: Connection refused
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:619)
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:216)
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:202)
at sun.rmi.server.UnicastRef.invoke(UnicastRef.java:129)
at javax.management.remote.rmi.RMIServerImpl_Stub.newClient(Unknown Source)
at javax.management.remote.rmi.RMIConnector.getConnection(RMIConnector.java:2392)
at javax.management.remote.rmi.RMIConnector.connect(RMIConnector.java:308)
at javax.management.remote.JMXConnectorFactory.connect(JMXConnectorFactory.java:268)
at org.archive.jmx.Client.execute(Client.java:225)
at org.archive.jmx.Client.main(Client.java:154)
Caused by: java.net.ConnectException: Connection refused
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:579)
at java.net.Socket.connect(Socket.java:528)
at java.net.Socket.<init>(Socket.java:425)
at java.net.Socket.<init>(Socket.java:208)
at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:40)
at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:147)
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:613)
... 9 more
又用cmdline-jmxclient-0.10.3.jar在tomcat服務器本地來調用。結果顯示沒問題。
java -jar cmdline-jmxclient-0.10.3.jar - 192.168.2.62:12345 java.lang:type=Memory NonHeapMemoryUsage
12/28/2016 14:44:07 +0800 org.archive.jmx.Client NonHeapMemoryUsage:
committed: 539426816
init: 539426816
max: 587202560
used: 17116088
防火牆已關閉，初步判斷是tomcat的catalina.sh中CATALINA_OPTS的配置問題。
CATALINA_OPTS配置如下：
CATALINA_OPTS="$CATALINA_OPTS
-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.port=12345"
經查詢 -Djava.rmi.server.hostname需要設置tomcat server的ip 遠端zabbix server才能找到，不至於去找本機的127.0.0.1
修改CATALINA_OPTS爲：
CATALINA_OPTS="$CATALINA_OPTS
-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.authenticate=false
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.port=12345
-Djava.rmi.server.hostname=192.168.2.62"
重啓tomcat
在zabbix server 測試無誤：
java -jar cmdline-jmxclient-0.10.3.jar - 192.168.2.62:12345 java.lang:type=Memory NonHeapMemoryUsage
12/28/2016 14:44:13 +0800 org.archive.jmx.Client NonHeapMemoryUsage:
committed: 539426816
init: 539426816
max: 587202560
used: 17127656
刷新zabbix web ,可以看到JMX由紅變綠，正常。
bingo.