of 25 /25
1 Web Server Administration Chapter 9 Extending the Web Environment


Embed Size (px)



Text of Cita310chap09

  • 1. Web Server Administration Chapter 9 Extending the Web Environment

2. Overview

  • Understand File Transfer Protocol (FTP) services
  • Install and configure an FTP server in Windows
  • Install and configure an FTP server in Linux
  • Understand News servers
  • Configure remote access to a server
  • Understand streaming media servers
  • Understand e-commerce software

3. Understanding FTP Services

  • FTP is used to transfer files from a server to a client (download) and transfer files from a client to a server (upload)
  • FTP client is the browser
    • Also command-line and GUI clients
  • FTP servers can operate as anonymous servers or they can require a valid logon
    • Typically, they are anonymous
    • FTP servers are not secure; user names and passwords are not sent encrypted

4. Understanding FTP Services

  • The client connects to port 21 (control port)
  • Port 20 (data port) is used to tell the client which unprivileged port to use for data transfer
  • The above describes passive mode FTP, the most common type

5. Communicating with FTP dir *.rpm Displays the long listing of files and their properties, such as the size and date the file was created dirfilenames ls *.rpm Displays filenames and can use wildcards lsfilenames bye Closes the connection and exits the FTP client quit or bye close Closes the connection but does not exit the FTP client close open Once the FTP client has been started, opens a connection openhost ftp Initiates a connection to FTP server ftphost Example Description Command 6. Communicating with FTP prompt Starts prompting prompt prompt no Stops prompting for each file when used before you usemgetormput prompt no mput *.tif Uploads multiple files; used with wildcards mputfilenames mget sendmail*.rpm Downloads multiple files; used with wildcards Mgetfilenames put testapp.zip Uploads a single file putfilename get test.rpm Downloads a single file getfilename ascii Transfer files in text mode ascii binary Transfer files in binary mode binary Example Description Command 7. Communicating with FTP help mget Finds very brief help on FTP commands; if used without a reference to a command, it will give you a list of commands available helpcommand pwd Displays the current directory on the server pwd lcd /docs Moves to another directory on the clientlcddirectory cd /software Moves to another directory on the FTP server cddirectory hash Displays a hash symbol as files are being downloaded hash Example Description Command 8. Install and Configure Windows FTP Server

  • Windows component
    • Part of IIS
  • Configured through Internet Information Services (IIS) Manager

9. Configure FTP Messages

  • Banner appears when client connects
  • Welcome appears when logged on
  • Exit appears when client exits from server
  • Maximum connections appears when limit is reached and client cannot connect

10. Install FTP in Linux

  • The wu-ftpd FTP server was developed by Washington University
  • Once the rpm is installed, enable FTP
    • chkconfig wu-ftpd on
    • Restart xinetd service to recognize change
      • service xinetd restart

11. Configure /etc/ftpaccess

  • The /etc/ftpaccess file is the main configuration file
  • By default, users with IDs less than or equal to 99 are not allowed
    • They are for system users and daemons
    • Because the ftp user is a system user, you have to allow it with
      • allow-uid ftp
      • allow-gid ftp

12. Configure /etc/ftpaccess

  • Limit user to a maximum of five failed logons before a disconnect
    • loginfails 5
  • Check for password that conforms to e-mail address
    • passwd-check rfc822 warn

13. Control Access

  • Set up user classes
    • class all real,guest,anonymous *
    • class local real
  • Set limits for class
    • file-limit out 25 anonymous
    • file-limit in 10 local
    • byte-limit out 2000000 anonymous

14. Configure Messages

  • To receive notice that a readme file exists at login or any current working directory (cwd)
    • readme README* login
    • readme README* cwd=*
  • To display a message when a user logs on or moves to a directory
    • message /welcome.msg login
    • message .messagecwd=*
  • To create a banner message when client connects
    • banner /etc/banner.txt

15. Understanding News Servers

  • News servers allow threaded discussions
  • You post messages in a newsgroup
  • A newsgroup focuses on a single topic
  • There are more than 40,000 public newsgroups
  • There are hundreds of gigabytes of information generated per day
  • News servers can be set up for use within an organization

16. Configuring Telnet in Linux

  • By default, telnet is installed but not enabled
    • chkconfig telnet on
    • service xinetd restart
  • Telnet should not be used in a non-secure environment such as over the Internet because user names and passwords are not encrypted
    • ssh is a secure replacement (described in Chapter 10)
  • You cannot log on as root
    • However, you can log on as another user and "su root"

17. Telnet and Windows

  • Telnet is not popular in Windows because telnet is text-based and Windows relies on a GUI
    • However, there are many command-line utilities that can be used, especially in Windows Server 2003
  • Before Windows, Microsoft networking depended on a single commandnetwith many options
  • cacls can be used to alter permissions
  • netsh starts a networking shell which allows you to configure and display many network-related items

18. Common net Commands net use g: eb1docs Maps a drivenet usedrive: omputershare net share docs=c:docs Shares a folder net sharename=location net start "FTP Publishing Service" Starts a service net startservice net user mnoia Displays user information net userusername net user Lists all users net userExample Description Command 19. cacls options

  • The format is: caclsfile or folder name [options]

Revokes permission /ruser /e As above, except permissions are replaced /puser:perm Grants a user specific permissions Permissions are:f (full control) r (read) w (write) c (change) n (none) /guser:perm Changes all subfolders /t Changes instead of replaces permission /e Description Option 20. netsh Examples

  • Create a text file with commands to re-create the IP configuration
    • netsh interface ip dump
  • Ping the gateway IP address of each NIC
    • netsh diag ping gateway
  • In Windows Server 2003
    • Display errors in system log
    • Manage network monitor and performance
    • Defragment a drive
    • Shut down a server

21. Terminal Services in Windows

  • GUI-based access to a server
  • Can be used for remote administration or running applications remotely
    • In Windows 2000, you select remote administration on installation
    • In Windows Server 2003, it is installed already and you have to enable it
  • Client software is included in Windows Server 2003 and Windows XP
  • You have to install client software for Windows 2000

22. Understanding Streaming Media Services

  • Used to transfer video and audio
  • By default, UDP is used
    • Although TCP and HTTP can be used because of firewall issues in an organization
  • No single standard exists as is true with SMTP, HTTP, POP3, and others
  • Broadcast methods
    • unicast each packet is sent individually to each client
    • multicast each packet is sent to many clients

23. Understanding Streaming Media Services

  • Helix Universal Server from Real Networks is popular
    • Recognizes both Real Networks protocols (RTSP, PNA) and the Microsoft protocol (MMS)
  • Windows Media Services is a Windows component
    • Creates a folder called ASFRoot to store Advanced Streaming Format (ASF) files

24. Understanding E-Commerce Servers

  • Can be as simple as a product list and a shopping cart
  • Can be as complex as amazon.com or dell.com
  • Microsoft Commerce Server is an add-on to IIS
    • Incorporates a number of features required for a typical e-commerce site
    • Highly customizable

25. Summary

  • Use FTP to transfer files
  • You use News servers to set up threaded discussions on a variety of topics
  • Telnet and Windows Terminal Services allow you to remotely administer a server
  • Streaming media servers are used for video and audio
  • E-commerce servers focus on selling and in general, communicating with customers