The Netcon/Netcontool utility

Introduction

The Netcon/Netcontool utilities allow you to connect to an E10000 domain as a master console. They replace the keyboard and monitor or serial port A connection used by other SPARC systems.

For a netcon session, typically you log in to the SSP machine as user ssp, and enter the netcon command in an SSP window. For example: 

ssp% domain_switch domain_name
ssp% netcon

This action changes the window in which you run the netcon command into a netcon window for the domain specified by the domain_switch command. Multiple netcon windows can be opened simultaneously, but only one at a time can have write privileges to a specific domain. When a netcon window is in read-only mode, you can view messages from the netcon window, but you cannot enter any commands.

You can specify the netcon option -g for Unlocked Write permission, -l for Locked Write permission, -f to force Exclusive Session mode, or -r for read only mode. See the netcon man page for an explanation of how netcon behaves if you do not specify any of these arguments.

If you have write permission, you can enter commands. In addition, you can enter special commands prefixed by atilde (~) to perform the functions offered by the netcontool window.

Overview of netcontool

The netcontool GUI program provides the buttons shown below:

The following table explains the netcontool buttons:

Table - netcontool buttons
ButtonDescription

Configure

Displays the Console Configuration window.

Connect

Displays the netcon window and initiates the connection process.

Disconnect

Disconnects the console window from the domain and removes the console window. The netcontool window is still available so that you can reconfigure for another connect session.

OBP/kadb

Breaks to the OpenBoot PROM (OBP) or kadb programs.

JTAG

Toggles the SSP-to-platform connection between a network connection and a JTAG connection.

Locked Write, Unlocked Write, and Exclusive Write

Request the corresponding mode for the console window. For an explanation of the meaning of these modes.

Release Write

Releases write access and places the console in read only mode.

Status

Displays information about all open consoles that are connected to the same domain as the current session, as well as the connection type currently used.

Help

Displays information about the netcontool window.

Exit

Exits the program and removes the netcon window if it is still open.

To Display a netcon Window From a netcontool Window

  1. Firstly allow your workstation to accept the GUI display by entering the following at the prompt: 
         % xhost +

  2. Next telnet to the required ssp and enter the folowing, substituting the IP with that for your workstation. This will cause the Netcontool GUI to be displayed on your workstation: 
         ssp% domain_switch domain_name
     ssp% setenv DISPLAY 192.168.56.60:0
     ssp% netcontool &

  3. Click the Connect button in the netcontool window.

    This displays the netcon window. Netcon attempts to connect to your chosen domain. If no error occurs, the netcon window is displayed directly beneath the netcontool window. Note that these are two separate windows, although they can affect each other. You can view messages in the console window and, if you have write permission, enter commands.

To Display a netcon Window From the Command Line

  1. Log in to the SSP as user ssp.

  2. Type:

         ssp% domain_switch domain_name
     ssp% netcon

    For more information about the netcon command options, refer to the netcon man page.

To Exit from a netcon Window

  1. Type the following escape sequence (tilde (~) followed by a full-stop) in the netcon window:

         # ~.

If you enter the tilde full-stop sequence locally at the SSP workstation or remotely through a telnet session, your netcon session is terminated and the window returns to its previous state. However, if you enter the tilde full-stop sequence remotely through an rlogin session, the netcon session is terminated and the rlogin window is deleted as well. This is because the tilde full-stop sequence is recognized by rlogin as an exit command. If you want to avoid this behavior, you can use the sequence ~~., that is tilde tilde full-stop, to exit from a netcon window running inside of an rlogin session. For more information about escape sequences, see the netcon manual page.

To Display a netcontool Window From the Command Line

  1. Log in to the SSP as user ssp.

  2. Type:

         ssp% domain_switch domain_name
     ssp% netcontool &

To Display the netcontool Window From Hostview

  1. Select a board from the domain for which you want to display a netcontool window by clicking on that board with the left mouse button.

  2. Select Terminal netcontool.

  3. In the netcontool window, click the Connect button.

    The netcontool window is displayed beneath the netcontool buttons.

    netcontool Window in Hostview

To Configure the netcontool Window

  1. Click the Configure button if you want to configure the netcontool window before you display a netcon window.

    The Console Configuration window is displayed

                    
    netcontool Console Configuration Window

  2. Select the session type in the left panel, and the terminal emulation type in the right panel.

  3. When you are satisfied with the contents of the window, you click Done to accept the settings and dismiss the window, or click Apply to accept the settings without dismissing the window.

    The following table contains the options in the Console Configuration. window.

    Table - Console Configuration
    ConsoleOptions

    Default Session

    This causes the default type of session to be started. If no other session is running, the default is unlocked write mode. If any other session is running, the default is read only mode.

    Read Only Session

    Displays a console window where you can view output from a domain, but you cannot enter commands.

    Unlocked Write Session

    Attempts to display a netcon window with unlocked write permission. If this attempt succeeds, you can enter commands into the console window, but your write permission is taken away whenever another user requests Unlocked Write, Locked Write, or Exclusive Session permission for the same domain.

    • If another user currently has Unlocked Write permission, it is changed to read-only permission, and you are granted Unlocked Write permission.

    • If another user currently has Locked Write permission, you are granted read-only permission.

    • If another user currently has Exclusive Session permission, you are not allowed to display a netcon window.

    • If you are granted Unlocked Write permission and another user requests Unlocked Write or Locked Write permission, you are notified and your permission is changed to read only. You can attempt to reestablish Unlocked Write permission at any time, subject to the same constraints as your initial attempt to gain Unlocked Write permission.

    Locked Write

    Attempts to display a console window with Locked Write permission.

    • If you are granted Locked Write permission, no other user can remove your write permission unless they request Exclusive Session permission.

    • If another user currently has Locked Write permission, you are granted read-only permission.

    • If another user currently has Locked Write permission, you are granted read-only permission.

    • If another user currently has Exclusive Session permission, you are not allowed to display a netcon window.

    Exclusive Session

    Displays a console window with Locked Write permission, terminates all other open console sessions for this domain, and prevents new console sessions for this domain from being started. You can change back to multiple session mode by clicking the Release Write button to release write access, or by clicking the Disconnect button to terminate your console session for the domain. You can also simply quit from the console window (using the Control menu of the window). You are not granted Exclusive Session permission if any other user currently has exclusive session permission.

    TerminalEmulationType

    The netcon window is brought up in the specified type of window. The default is xterm. dtterm is only available if you are running the Common Desktop Environment (CDE), otherwise it is grayed out. You can also use shelltool or cmdtool.

netcon Communications

netcon uses two distinct paths for communicating console input/output between the SSP and a domain: the standard network interface and the CBE interface. Usually, when the domain is up and running, console traffic flows over the network. If the local network becomes inoperable, all interactive access to the domain is lost and, for example, telnet, rlogin, and netcon sessions hang. In this case, you can switch to the CBE interface and access the host's console window. To perform this switch, use the ~ = command in the netcon window.

netcon Message Logging

Certain messages sent from the kernel are not displayed in the syslog messages file, such as OpenBoot messages, panic messages, and some console messages. The reason for this is that syslogd must run on the host to log the messages, and this is not possible when a panic occurs, nor is it possible at certain times during the boot sequence. Moreover, panic dumps often fail, so these types of messages may not even appear in a dump file to help you determine the cause of the failure.

However, you can capture all output displayed on an active netcon console through the LOCAL1 facility of syslog and the SSP machine_server. This functionality is enabled through the /etc/syslog.conf and $SSPLOGGER/.logger files. When enabled, netcon session output is recorded in file $SSPLOGGER/domain_name/netcon, where $SUNW_HOSTNAME is set to the hostname for the domain. By default, this functionality is disabled.

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