Franske ITC-2480 Lab 11

Lab Procedure

Prerequisites

1. Open an SSH console to your Linux system using the PuTTY software, login with your standard user account

Exploring /proc

1. To start this lab, go to /proc in putty. /proc is a very special folder is its a virtual filesystem. Its sometimes referred to as a process information pseudo-file system. The reason is that all of the files in /proc are not real files, but runtime and system information.
2. For example, now that you are in /proc, run cat cpuinfo. Notice how the output tells your information about the CPU that is running the Virtual Machine. /proc is used not only to get hardware and runtime information, but it can also be used to tweak kernel settings. Look back on Lab 10 and notice how we echoed a number to a file in /proc to enable packet forwarding.
3. There are a few files in /proc you should get to know:
   • /proc/cpuinfo = Shows you the CPU info for your machine.
   • /proc/modules = Shows you the currently enabled kernel modules that are active on your kernel.
   • /proc/cmdline = Shows you the boot arguements used to boot your kernel.
   • /proc/version = Shows you your kernel version.
4. It is important to note that some of these files have commands tied to them, for example.
   • /proc/modules = lsmod
   • /proc/mounts = mount
   • /proc/version = uname -a
5. Normally it is best to use the command version to lookup the information as it is normally formatted to be easier to read and understand.
6. Explore around with these commands and find the differences between the command line and file output versions.

Exploring /dev

1. now change directories to /dev and list the files. Notice that there are ALOT, but don't worry there is organization in the mess. Each file, like in /proc, is actually a device or interface on the machine. Here is a list of the most common interfaces you will see:
   • /dev/sd* = SATA Hard Drives/Disk Drives
   • /dev/hd* = IDE Hard Drives/Disk Drives
   • /dev/ttyS* = Serial Interfaces on your PC.
   • /dev/tty* = Virtual Consoles, similar to the one you are using to enter commands. Mostly used by background programs or services.
2. There are also some commands you should learn that will help you with detecting, and looking up devices:
   • lsusb = List USB Devices (Bus, Device, ID, and advertised vendor)
   • lspci = List PCI Devices (Bus, Type, Advertised Name, Revision)
   • dmesg = Display or Driver Message. This shows kernel messages that are normally linked to adding, or removing devices.