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Exam objective 2.203.1 has a weight of 3, and verifies that candidates are able to configure and navigate the standard file system. This includes configuring and mounting various file systems and manipulating file systems to adjust for disk space requirements for device additions. This includes the file systems table and the tools for handling swap partitions. Most of this information was covered in previous lessons. FSTab, the File Systems Table, was described earlier. It's the list of file systems that can be mounted. There are three ways to find out which file systems are currently mounted. First, as we saw earlier, the Mount command with no arguments will list the mounts. Notice that one of the mounted file systems is called Proc. It contains Process information. It's a pseudo file system that provides access to data structures inside executing programs, including the kernel. Every running process has an ID number, and the ID numbers appear as directory names inside the Proc directory, and you can use the files in these directories to find out information about the running process. You can also get information from inside the kernel. In particular, the kernel maintains an internal list of the mounted file systems, and you can see that list right here. All you have to do is list the contents of the file. These are the file systems that are currently mounted. And there is another way you can get this list. The MTab file in the ETC directory is a list of mounted file systems. Linux always seems to provide more than one way to do anything. Just pick the one you like and use it. You understand from previous lessons how Mount and UMount with the entries in FSTab. They work for all entries except the swap partitions, or swap files. You can turn swapping on and off with the Swap on and Swap off commands. The A option on the Swap on command starts swapping for every swapped file system listed in FSTab unless the NoAuto option has been specified. The Sync command synchronizes the disk with what's in memory. Any program that has some output pending, will have the output buffer flush to disk. This needs to be done when things are being shut down to prevent information from being lost. You can issue the Synch command, or Let Shutdown, or the Halt command to do it for you. You need to get the feel of how your system runs without swap space. Look in your FSTab file and find the device nodes for your swap space. Use the Swap off command to turn swapping off, then run some programs that crowd your system. You may want to try compiling, or maybe open a lot of windows, then when the programs have finished running, turn swapping on and run them again. Notice the difference in the time it takes. Use the CAT command to take a look at the contents of the files named Version and Swaps in the Proc directory.