Using a null modem cable

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To monitor what's happening on your Cobalt appliance (during bootup, an OS Restore, etc.), you can use the serial port (aka console).

The console functions much like a standard video card would in a regular PC, etc. -- during bootup, anything you would normally expect to see on a screen is echoed to the console instead. You can interact with the appliance as well -- boot into single user mode, change ROM settings, etc.

To utilize the console port, you need a DB-9 null modem cable, sometimes referred to as a Laplink cable (from the 1980s brand backup software system). You cannot use a standard serial cable -- it has to be a null modem cable (which "rolls" the transmit/receive wires inside between the end connectors, so that transmit on one end goes directly to receive on the other end). You can usually pick these cables up pretty inexpensively at any computer or electronic supply store. For more info than you ever wanted to know about null modem cables, go to http://www.nullmodem.com/NullModem.htm

1. Connect the cable to the console serial port on the appliance, and the serial port on your laptop or PC.

2. Start a terminal emulator on your laptop/PC (such as HyperTerm on Windows machines, or minicom on Linux)

3. Set the serial connection speed based on the appliance type. Most products use these settings:

  115200 bps, N-8-1 parity

The exceptions are MIPS products (Qube 2700, Qube 2, RaQ 1, RaQ 2, CacheRaQ 2) and RaQ 3. For them, the connection speed should be

  9600 bps, N-8-1 parity

3. Power up your appliance. You should immediately see output in your terminal emulator. If you do not, it's possible the serial console is disabled. Power down your appliance, then hold in the password reset button with a paperclip and power the appliance back on again. You should see a message in the LCD "SERIAL CONSOLE ON" and output should appear in the terminal emulator. When it does, you can release the password reset switch.

If you see "SERIAL CONSOLE OFF" in the LCD, the console was enabled. Power off the appliance, then back on again per step 3, to toggle the console setting.

If you don't see any output and you know the console is enabled, double check you are using the proper serial port on the appliance. You want the first one (normally marked with the Roman numeral I or a single dot); the second port is typically used for UPS communication or other serial devices. Also doublecheck your baud rate, etc. If you see some output but it's garbled, your baud rate is set incorrectly.

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