我正在使用 Cisco Netflow Collector 软件，它正在按预期收集 netflow 数据，直到服务器管理员禁用 iptables 并且安全管理员为服务器启用了防火墙。现在它给出了以下异常。
收集器在内部/私有服务器上运行，并且 Cisco NFC 许可证绑定到公共 ip，因此主机名在 /etc/hosts 文件中设置为公共 ip
[2015-09-29 12:03:41 GMT+05:30] INFO com.cisco.nfc.cnsxml.CNSXMLMonitor - Starting CNS/XML Interface for NFC 6.0.0 [standard image, build 31]...
[2015-09-29 12:06:51 GMT+05:30] ERROR com.cisco.nfc.cnsxml.CNSXMLMonitor - Could not start CNS Event Service transport
java.rmi.ConnectException: Connection refused to host: <public IP>; nested exception is:
java.net.ConnectException: Connection timed out
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:574)
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:185)
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:171)
at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:306)
at sun.rmi.registry.RegistryImpl_Stub.rebind(Unknown Source)
at java.rmi.Naming.rebind(Naming.java:160)
at com.cisco.nfc.cnsxml.CNSXMLMonitor.<init>(CNSXMLMonitor.java:163)
at com.cisco.nfc.cnsxml.CNSXMLMonitor.main(CNSXMLMonitor.java:192)
Caused by: java.net.ConnectException: Connection timed out
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
at java.net.Socket.connect(Socket.java:519)
at java.net.Socket.connect(Socket.java:469)
at java.net.Socket.<init>(Socket.java:366)
at java.net.Socket.<init>(Socket.java:179)
at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:22)
at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:128)
at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:569)
... 7 more
sec 管理员已允许端口 22 和 1099，但仍抛出上述异常。我需要更改服务器或防火墙中的配置吗？