Classroom Management network FAQ and troubleshooting

Transcription

1 Classroom Management network FAQ and troubleshooting Author: Grant Kelly

2 The concepts in this document are intended to be a guide to aid in the resolution of certain issues that occur with using the Classroom Management software in some common network configurations that have come to our attention. Intel nor the author assume any responsibility for any changes made to a network as a result of consulting this document. Intel and the author advise that you consult with your network management team as to the possible repercussions that may occur as a result of making any changes suggested in this document. General Network configuration: There are a few common issues and questions that occur when using the Classroom Management. Classroom Management uses multicast for communication between the Teacher PC and CMPCs. For the purposes of this document, multicast is best thought of as similar to broadcast traffic and therefore subject to the same limitations. Broadcasts are limited to broadcast domains and routers are generally the devices used to limit these broadcast domains. In general terms, a broadcast domain is a single subnet and these can correspond to an individual VLAN. Quite often, large networks are divided into several VLANs for multiple reasons. Security, management and limiting broadcasts domains are just a few reasons. Generally, VLANs are assigned differing subnets and a path of communication may or may not exist between separate VLANs. This path is controlled by some type of routing device. As mentioned above, routers are the devices that separate broadcast domains. The occurrence of these network topologies has generated the following questions: A. I can t see my students CMPCs on my Teacher PC. I have a student network and a teacher network that are on separate VLANs. The Teacher PC is connected to the teacher network and the CMPCs are connected to the student network. Will this work? a. This will not work without using the Name and Connectivity server software (install procedure defined later in this guide). The Teacher PC and the CMPC must be on the same subnet and most likely, the same VLAN. Configuring the Teacher PC to connect to the student network is the most common solution to this. B. How large should I make my network (what subnet mask should I use)? a. Best practices should dictate the size of the network and topology. The only constraint, with regards to Classroom Management, is that the Teacher PCs and the CMPCs need to be on the same subnet when not using the Name and Connectivity server. For example: If you have 450 CMPCs and 23 Teacher PCs on one network and you want them all to communicate with each other, foregoing any other constraints, the network could use a 23 bit ( ) subnet mask. This would allow 510 IP addresses to exist on the same network/broadcast domain.

3 Cisco Wireless LAN Controller (WLC): There is an issue that exists with the default configuration of a Cisco Wireless LAN Controller (WLC) that appears to be persistent across all models of the WLC. By default, the WLC does not support the type of communication used by Classroom Management thereby preventing the CMPCs from connecting to the Teacher PC. This can be resolved by enabling multicast on the controller and disabling IGMP snooping. Testing revealed that IGMP snooping effects are not consistent and seem to have more effect on H-REAP groups. As seen in the screenshot above, click on Controller in the top menu bar and then Multicast in the left menu bar. Check the box to the right of Enable Global Multicast Mode and remove (if it exists) the check in the box to the right of Enable IGMP Snooping.

4 Cisco Autonomous Access Points: There is an issue that exists with some Cisco Autonomous Access Points that prevent the CMPCs from associating with the Teacher PC that is caused by IGMP snooping. In an effort to manage some communications, IGMP snooping attempts to aggregate that communication into groups. This causes the multicast communication between the CMPCs and the Teacher PC to fail. This is easily resolved by disabling IGMP snooping in the global configuration of the Cisco Access Points. As seen in the screenshot above, connect to the access point either via a console cable, SSH session or telnet session. At an enable prompt, type configure terminal and press enter. Enter the command no ip igmp snooping and press enter. Exit out of configuration mode and make certain to save the configuration to the startup configuration so that it is persistent across a reboot of the access point.

5 Name and Connectivity server install: The Name and Connectivity server software allows the Classroom Management software to function across multiple networks that have clear traffic paths between each other. It acts as an intermediary registration and query point for the Student PCs to register to and the Teacher PCs to query from. The install for the Name and Connectivity server is included in the full install that is typically used to install the Teacher (Tutor) console. The Name and Connectivity server should reside on a PC or server accessible to both Teacher and Student subnets. If the Name and Connectivity server is to be installed on a Teacher PC, the Teacher PC should utilize a statically assigned address or a DHCP reservation should be created as to insure that the service is always available at the same address. Install of Name and Connectivity server: Note the IP address of the device that you are installing the Name and Connectivity server on. This is easily accomplished by running a command prompt and issuing the ipconfig command. You will need the IP address later in the configuration of the Teacher and Student PCs. Launch the setup application for the Classroom Management and choose the appropriate install type. In the example below, the Tutor console had been installed and thus a Modify installation type was choosen.

6 Place the checkmark on Name and Connectivity Server and click Next and finish the prompts to complete the installation.

7 Upon the completion of the install, the Classroom Management Gateway Configuration Utility configuration screen will appear. The default options, including the port definition can remain unchanged unless there is another service that is already installed on the target device that listens on that same port. The port can be changed freely. Simply note the port used as it will be necessary to use that port in the configuration of the Teacher and Student PCs.

8 Click on the Keys tab of the configuration utility window and add a new key. This will create the encryption key to be used between the Student/Teacher PCs and the Name and Connectivity server.

9 Clicking Add will bring up the following window: Enter a meaningful description in the Description: field and click the Set button to bring up the following window: Enter a password of your choice and confirm the password in the provided fields. The password must be at least 7 characters in length. You will need to enter this password on the Student and Teacher PCs as part of the configuration.

10 Click OK on the Gateway Key window, click OK on the Add Gateway Key window and OK or Apply on the Classroom Management Gateway Configuration Utility window. When prompted with Would you like to apply changes to the Gateway?, click Yes. Verify that the Classroom Management Gateway Console is running by locating the icon in the systray and verifying that is has a green check in the icon.

11 Configure Teacher and Student PCs to use the Name and Connectivity server: To properly utilize the Name and Connectivity server, the Student and Teacher PCs must be configured to register to and query from the service. The Teacher and the Student PCs will default to broadcast resolution without this configuration. Configure the Teacher PC to use the Name and Connectivity server: Launch the Classroom Management Tutor Console, navigate through the welcome screen if enabled and proceed to the New Class window. Choose the appropriate room/class to use. The below depicts a default install with a room named Eval. Click OK.

12 Click on School and then Configuration on the ensuing menu.

13 The Settings for Classroom Management windows will appear. Navigate to the Network and Wireless Settings and locate the Use Name & Connectivity Server check box. Place a check in the box and click on Settings to the right.

14 The Name & Connectivity Server configuration window will appear. Enter the IP address of the Name and Connectivity server in the Address: dialog box, the port in the Port: dialog box and click Set to enter the same password used above in the Gateway Key configuration of the Name and Connectivity Server. Click OK on the Security window, click OK on the Name & Connectivity Server windows and answer Yes to apply the changes.

15 Configure the Student PC to use the Name and Connectivity server: The Student configuration requires you to navigate the file system of the PC and locate pcicfgui.exe and launch that application. The application writes a configuration file that can then be copied to all other Student PCs that will be using the same Name and Connectivity server. See Copying the configuration file below. The application can be located at the following location for a 64 bit OS install: The path is C:\Program Files (x86)\intel(r) Education Software\Classroom Management for x64 systems. The path is C:\Program Files\Intel(R) Education Software\Classroom Management for x86 systems.

16 Locate and double click the aforementioned file and the following windows will appear.

17 Place the check in the Use Name & Connectivity Server check box and click Configure. Enter the appropriate information in the Address: dialog box, the Port: dialog box and click Set... to enter the key. Click OK on the Security window, click OK on the Name & Connectivity Server windows and answer Yes to apply the changes.

18 Copy the configuration file: The aforementioned process to configure Student PCs can be daunting in large deployments and thus another method is available to expedite the procedure. The aforementioned application, pcicfgui.exe, alters a configuration settings file called Client32.ini. This file is located in the same directory as the utility: C:\Program Files (x86)\intel(r) Education Software\Classroom Management for x64 systems. C:\Program Files\Intel(R) Education Software\Classroom Management for x86 systems. Locate Client32.ini and copy the file to any other Student PC that you wish to use the same mode, room/class name and Name & Connectivity Server and reboot the PC. Upon restart, the Classroom Management agent will restart and read the configuration from this file.

19 Verify the Name and Connectivity server: You can verify that the Student and the Teacher PCs are registering to the Name and Connectivity server by double clicking the Classroom Management Gateway Console icon in the systray and inspecting the window that appears. Depicted below are two Student PCs and the Teacher PC all using a room called Eval.