User manual MATLAB MATLAB DISTRIBUTED COMPUTING SERVER 4 SYSTEM ADMINISTRATORS GUIDE

[. . . ] MATLAB® Distributed Computing ServerTM 4 System Administrator's Guide How to Contact The MathWorks Web Newsgroup www. mathworks. com/contact_TS. html Technical Support www. mathworks. com comp. soft-sys. matlab suggest@mathworks. com bugs@mathworks. com doc@mathworks. com service@mathworks. com info@mathworks. com Product enhancement suggestions Bug reports Documentation error reports Order status, license renewals, passcodes Sales, pricing, and general information 508-647-7000 (Phone) 508-647-7001 (Fax) The MathWorks, Inc. 3 Apple Hill Drive Natick, MA 01760-2098 For contact information about worldwide offices, see the MathWorks Web site. MATLAB® Distributed Computing ServerTM System Administrator's Guide © COPYRIGHT 2005­2010 by The MathWorks, Inc. The software described in this document is furnished under a license agreement. The software may be used or copied only under the terms of the license agreement. [. . . ] Use the function to determine what MDCS processes are running on the local host, and which are accessible from remote hosts. If a worker on hostA cannot register with its job manager on hostB, run nodestatus on both hosts to see what each can see on hostB. On hostB, execute: nodestatus -remotehose hostB Then on hostA, run exactly the same command: nodestatus -remotehose hostB The results should be the same, showing the same listing of job managers and workers. If the output indicates problems, run the command again with a higher information level to receive more detailed information: nodestatus -remotehose hostB -infolevel 3 Using a GUI You can diagnose some communications problems using Admin Center. If you cannot successfully add hosts to the listing by specifying host name, you can use their IP addresses instead (see "Adding Hosts" on page 3-3). If you suspect any communications problems, in the Admin Center GUI click Test Connectivity (see "Testing Connectivity" on page 3-9). This testing verifies that the nodes can identify each other and allow their processes to communicate with each other. 2-24 Troubleshooting Verifying Multicast Communications Note Although the current version of the parallel computing products continues to support multicast communications between its processes, multicast is not recommended and might not be supported in future releases. Multicast, unlike TCP/IP or UDP, is a subscription-based protocol where a number of machines on a network indicate to the network their interest in particular packets originating somewhere on that network. By contrast, both UDP and TCP packets are always bound for a single machine, usually indicated by its IP address. The main tools for investigating this type of packet are: · tcpdump for UNIX operating systems · winpcap and ethereal for Microsoft Windows operating systems · A JavaTM class included with the parallel computing products. The Java class is called com. mathworks. toolbox. distcomp. test. MulticastTester. Both its static main method and its constructor take two input arguments: the multicast group to join and the port number to use. This Java class has a number of simple methods to attempt to join a specified multicast group. Once the class has successfully joined the group, it has methods to send messages to the group, listen for messages from the group, and display what it receives. You can use this class both from a command-line call to Java software and inside MATLAB. From a shell prompt (assuming that java is on your path), type java -cp distcomp. jar com. mathworks. toolbox. distcomp. test. MulticastTester You should see an output something like this: 0 : host1name : 0 1 : host2name : 0 2-25 2 Network Administration The following example shows how to use the Java class inside MATLAB. Start MATLAB on two machines (e. g. , host1name and host2name) for which you want to test multicast. In each MATLAB session, enter the following commands: m = com. mathworks. toolbox. distcomp. test. MulticastTester('239. 1. 1. 1', 9999); m. startSendingThread; m. startListeningThread; These instructions cause each MATLAB session to issue a stream of multicast test packets, and to listen for test packets. If multicast is working between the machines, you see a stream of lines like the following: 0 1 2 3 : : : : host1name host2name host2name host2name : : : : 0 0 1 2 The number on the left in each string is the line number for the received packet. The text in the center is the host from which the packet is received. The number on the right is the packet number sent by the sending host. It is normal for a host to report a test packet from itself. [. . . ] job manager lookup process The process that allows clients, workers, and job managers to find each other. It starts automatically when the job manager starts. lab When workers start, they work independently by default. They can then connect to each other and work together as peers, and are then referred to as labs. LOGDIR The name of the parameter in the mdce_def file that defines the directory where logs are stored. [. . . ]