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Standard Operating and Maintenance Procedures. Guide to Operating Systems Second Edition. Objectives. After reading this chapter and completing the exercises you will be able to: Explain file system maintenance techniques for different operating systems
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Standard Operating and Maintenance Procedures Guide to Operating Systems Second Edition Chapter 10
Objectives After reading this chapter and completing the exercises you will be able to: • Explain file system maintenance techniques for different operating systems • Perform regular file system maintenance by finding and deleting unused files and directories • Perform disk maintenance that includes defragmenting, relocating files and folders, running disk and file repair utilities, and selection RAID options Chapter 10
Objectives After reading this chapter and completing the exercises you will be able to: • Set up and perform disk, directory and file backups • Explain how to install software for best performance • Tune operating systems for optimal performance Chapter 10
File System Maintenance • Successful file system maintenance is closely linked to the file structure on a computer • Some basic rules for creating a file structure include: • Keep a manageable number of directories in the root directory • Keep operating system files in the default directories recommended by the vendor • Keep different versions of software in their own directories • Keep data files in directories on the basis of their functions • Design home directories to match the functions of users in an organization • Group files with similar security needs within the same directories Chapter 10
Example Applications Directories and Subdirectories • Well-organized directories and subdirectories enable you to have a relatively small number of main directories in the root Chapter 10
File System Maintenance • The directories in the following example are as follows: • bin for user programs and utilities (binary files) • lib for libraries • usr for user’s files and user programs • var for files in which the content often varies, or that are only used temporarily • tmp for files used only temporarily • dev for devices • mnt for floppy drive, cd-rom drives, and other removable media that can be mounted Chapter 10
File System Maintenance • etc for system an configuration files • sbin for user programs and utilities (system binary files) • home for users’ home directories • proc for system resource tracking Chapter 10
File System Maintenance • Examples of important folders in the root of a Mac OS X system include: • Applications for software applications • Documents for storing documents • Library for library files that include fonts, preferences, and graphics, for instance • System for system files • Users for user accounts (containing a subfolder for each account) Chapter 10
File System Maintenance • In addition to folders off the root, each user account in Mac OS X contains folders such as: • Music for music files • Movies for movies that can be played on the computer • Pictures to sort picture files • Public for files to share with others over the network • Applications for applications used by the account • Library for support files, such as fonts used by the account • Documents for storing documents • Desktop for files that are on the user’s desktop Chapter 10
File System Maintenance • Operating system directories are typically placed in the root directory and have appropriate subdirectories under a main directory Chapter 10
Operating System Directories Chapter 10
File System Maintenance • There are several advantages to installing and leaving operating system files in the directories created by the operating system instead of trying to hide these files, or use other directory locations • One reason is that it is easier for others to help with computer problems a they arise • In most Windows-based systems, installed software is also tracked in the Registry, which contains configuration information, as well as information about individual components of a software installation Chapter 10
Examples of Windows-based Application Software Components Chapter 10
File System Maintenance • In Windows 95/98/Me and Windows NT/2000/XP, these vital files are kept in the operating system’s folder and subfolders • Some directory structures include special locations for data files • Home directories on a server often reflect the organizational structure Chapter 10
Finding and Deleting Files • A solid file structure on the computer makes it easier to find and delete unneeded files on a regular schedule • Most installations create a temporary directory and a set of temporary files that are stored in the temporary directory • Some software applications do not completely delete temporary files when the application installation is finished Chapter 10
Windows 95, 98, and Windows Me • Temporary files are equally problematic in Windows 95/98/Me • The software in many office suites enables you to create a backup or temporary file (sometimes multiple files) of a document or spreadsheet, for example • If you improperly exit from the office software, or improperly shut down the computer, these temporary files are not deleted Chapter 10
Windows 95, 98, and Windows Me • The temporary files often begin with a tilde (~) as a first character, or have a .tmp extension, and typically are found in the following places: • A temporary directory in the root, such as C:\Temp • A temporary directory in the Windows directory, such as C:\Windows\Temp • A DOS directory in the root (Windows 95) • A data directory in which word-processing, spreadsheets, or database files are stored • The applications directory that contains the executable file, which created the temporary file Chapter 10
Windows 95, 98, and Windows Me • Web browsers also write an impressive number of temporary Internet files that are not deleted, unless you set an expiration date, or delete them using a Windows utility or utility that comes with the Web browser • In most cases, the files can be deleted regularly, except for cookies that contain specialized information for accessing particular Web sites Chapter 10
Windows 95, 98, and Windows Me • There are three ways to search for and delete temporary files: • Use the Disk Cleanup utility • Use your browser tool (for Web-based temporary files only) • Use Windows Explorer Chapter 10
Windows 95, 98, and Windows Me • Finally, you can search for temporary files by using Windows Explorer • Open Windows Explorer from the Start button and Programs menu in Windows 95 and 98; or click Start, point to programs, point to Accessories, and click Windows Explorer in Windows Me • Click the Tools menu, move to Find, and click Files or Folders Chapter 10
Windows 95, 98, and Windows Me • To find temporary files created by applications, in the Find: All Files dialog box, enter *.tmp in the Named: text box; enter C:\ in the Look in: box; check the box to include subfolders; and click Find Now Chapter 10
Temporary Files Found in Windows 98 Chapter 10
Windows NT, 2000, and Windows XP • Temporary files accumulate in Windows NT, 2000, and XP systems, and can be deleted using utilities that are similar to those in other Windows-based systems • In Windows NT and Windows 2000, temporary files from applications are typically written to the \Temp, \Winnt\System32, and \Winnt\Temp folders • Temporary Internet files in Windows NT are in the \Winnt\Temporary Internet Files and \Winnt\Profiles\account\Temporary Internet Files (where account is the name of a particular account set up for a user) folders Chapter 10
Windows NT, 2000, and Windows XP • In Windows 2000, the temporary Internet files are stored in the \Documents and Settings\Administrator\Local Settings\Temporary Internet Files and \Documents and Settings\account\Local Settings\Temporary Internet Files folders • In Windows XP, the temporary files are located in the \Temp, \Windows\Temp, and \Windows\System32 folders • Windows XP temporary Internet files are in the \Documents and Settings\account\Local Settings\Temporary Internet Files Chapter 10
Windows NT, 2000, and Windows XP • There is no Disk Cleanup tool for Windows NT, which means hat the easiest way to find and delete unwanted files is by using Windows NT Explorer, following the same steps that you would use in Windows 98 • The best way to use the Disk Cleanup tool in Windows 2000 and Windows XP is to start it from Windows Explorer by opening Windows Explorer, right-clicking the disk you want to clean, clicking Properties, and clicking Disk Cleanup on the General tab Chapter 10
Windows NT, 2000, and Windows XP • When you start Disk Cleanup, it scans your disk to determine the amount of space that can be restored after cleaning specific types of files • The types of files that you can select to delete are: • Downloaded program files • Temporary Internet files • Recycle Bin • Temporary files Chapter 10
Windows NT, 2000, and Windows XP • Compress ld files (not really an option to delete, but to save space by compressing files) • Catalog files for the Content Indexer • Web Client/publisher temporary files (only in Windows XP) Chapter 10
UNIX • You can view UNIX files by using the ls command, along with one or more options for listing particular file qualities • Some of the options associated with this command in Red Hat Linux are as follows: • -a lists all files • -C formats the listing in columns for easier reading • -d lists directories • -f displays files in an unsorted list • The remainder are listed on page 509 of the textbook Chapter 10
UNIX • Files and folders are deleted in UNIX by using the remove (rm) command • The two options commonly added to the command are –i and –r • The –i or interactive option results in a query about if you really want to delete the file or directory; the –r or recursive command is used to delete the entire directory contents, including all subdirectories and files within a directory Chapter 10
UNIX • A file can be found by using the find command • Typical options used with find are as follows: • atime for last accessed time • ctime for last changed time • mtime for last modification time • name for the filename, including the use of wildcard searches • print to print the results of the find • size for file size • user to delete files by ownership Chapter 10
UNIX • Similar to the Windows-based and Mac OS GUI interface, the Red Hat Linux 7.2 GNOME interface offers a trash can from which deleted files can be retrieved • UNIX provides commands to help you assess the allocation of disk space • One command is df, which enables you to view information on the basis of the file system • On a UNIX computer that acts as a server, the administrator can set up disk quotas Chapter 10
UNIX Disk Quotas for Server Users Chapter 10
Mac OS • One particularly important reason for deleting files in the Mac OS is to make sure that you do not run out of disk space • The Mac OS provides an easy way to assess available disk space by simply checking the header information (in Mac OS versions up through 9.x) when you open the Macintosh HD window, or a window to display the contents of any folder • The Mac OS (including Mac OS X) has a Find utility on the File menu that can be used to find files that are no longer needed Chapter 10
Mac OS X Finder Chapter 10
NetWare • NetWare Administrator is one tool that is available to view and manage directories and files on the server • Another option for Windows-based NetWare clients is to use Network Neighborhood or My Network Places to view folder and file information, including information about properties • A third utility that can be very effective is called NDIR, and is run from a NetWare DOS window Chapter 10
NetWare • NDIR can also provide important information about directory space that is in use by using the commands shown on page 513 of the textbook • You can delete directories and files by using NetWare Administrator, or the delete (DEL) command in a DOS window • As is true for the Mac OS, NetWare files can be salvaged until they are purged Chapter 10
NetWare • Novell provides a utility called the NetWare Remote Manager, starting with version 6 of NetWare • This utility allows you to manage servers, applications, hardware, etc • You can also access the server console • This is all accomplished through your Web browser • Some of the options of this utility found on the main screen are listed in the textbook on page 514 Chapter 10
Maintaining Large and Small System Disks • In addition to finding and deleting unneeded files, there are other disk maintenance techniques that are valuable in terms of maintaining the integrity of files and ensuring disk performance • These include the following: • Defragmenting disks • Moving files to spread the load between multiple disks • Using disk utilities to repair damaged files • Deploying RAID techniques that extend the life of disks and provide disk redundancy Chapter 10
Defragmenting Disks • Hard disks in any operating system are subject to becoming fragmented over time • Fragmentation means that unused space develops between files and other information written on a disk • Defragmentation is the process of removing the empty pockets between files and other information on a hard disk drive • There are two ways to do this Chapter 10
Defragmenting Disks Chapter 10
Defragmenting Disks • The oldest method is to take a complete backup of a disk’s contents and perform a full restore • Some administrators also run a surface analysis of a disk before performing the full restore, as a means of finding damaged disk sectors and tracks • A second option that is usually easier than backing up and restoring a hard disk is to run a disk defragmentation tool Chapter 10
Defragmenting Disks • MS-DOS, Windows 3.x, Windows 95/98/Me, and Windows 2000/XP are examples of operating systems with built-in defragmentation utilities • In Windows 95/98/Me, defragmentation is accomplished through a Windows utility accessed from the Start button, Programs menu, and Accessories menu • In Windows 2000/XP, defragmentation is also accomplished through the Start button, Programs menu, Accessories, and System Tools menu • Windows NT 4.0 does not come with a defragmenting tool, but third-party software companies offer them Chapter 10
Disk Defragmenter in Windows XP Chapter 10
Defragmenting Disks • Defragmenting a Windows NT or Windows 2000 server can be an effective way to enhance performance, depending on how the server is used • Some versions of UNIX come with defragmenting tools, such as defragfs • The tools are limited in that they defragment and return to use existing empty space, but they may not rearrange files • The Mac OS is designed to minimize disk fragmentation, but third-party tools are available for system that experience high use Chapter 10
Moving Disk Files to Spread the Load • Another technique that can help extend the life of disk drives is to spread files evenly across disks when there is more than one disk • This technique is used mainly on computers with multiple-user access, such as servers, and on which there is frequent disk activity • Before files are moved, the server administrator examines disk and file activity to determine how to spread files across the disk drives to achieve even loading in terms of activity Chapter 10
Studying Resource Use in Windows XP via the Computer Management Tool Chapter 10
Using Disk Utilities to Repair Damaged Files • Some operating systems have utilities that enable you to repair damaged files and file links • Four examples of these utilities are: • Disk First Aid in the Mac OS • fsck and p_fsck in UNIX • chkdsk in MS-DOS, Windows 3.1, 3.11, 95, 98, NT, 2000, and XP • ScanDisk in MS-DOS, Windows 3.1, 3.11, 95, and 98 Chapter 10
Using Disk Utilities to Repair Damaged Files • Disk first aid is a MAC OS utility that verifies files, folders, and mounted disks • In MAC OS X, disk first aid is combined with the disk utility • The fsck utility in UNIX is used to check one or more file systems • Besides fsck, there is the p_fsck utility in some UNIX versions Chapter 10
Using Disk Utilities to Repair Damaged Files • The chkdsk disk utility runs in MS-DOS Prompt window in Windows 95/98/Me, or in the Command Prompt window in Windows NT/2000/XP • The Windows NT/2000/XP version of the utility is more powerful than the ones used in other versions of Microsoft Windows because it incorporates some of the features of ScanDisk • For versions of Windows other than Windows 98 and Windows Me, chkdsk can find and fix the items listed on pages 521 and 522 of the textbook Chapter 10