Linux Networking Cookbook

17.1. Preparing a Server for Serial Console Administration

Problem

You have an ordinary x86 server that you want to run headless, with serial console administration enabled, and you want to verify that all the pieces—hardware and software—are present. The serial console might or might not be your primary method of administering your server; regardless, you want to be sure that you can connect to it with a serial console.

Solution

First, check the BIOS for your server to see if it comes with serial console support already built-in. Most likely, a low-end PC won't, but higher-end and server-quality equipment might. If it does, follow the directions for your particular machine for setting it up for a serial console, and ignore the rest of this recipe.

If not, you'll need the following:

• Keyboard and monitor connected to the server until the serial connection is tested and ready.

• DB9 serial connector. If there is not one built-in to the motherboard, you can get a PCI serial port card inexpensively.

• agetty or mgetty utility.

• BIOS that allows the system to boot without an attached keyboard.

• Null-modem cable for direct connection to another PC.

• Kernel with console support built-in, not as a module.

• Hardware-controller modem if you want remote dial-in administration.

• Bootable rescue disk. (Always have one of these!)

Discussion

Serial port is one of those terms that covers a lot of ground. It means the physical connector, which on most PCs, is a male DB9 connector. It connects to a Universal Asynchronous ...