One of the most universally performed tasks by Linux systems administrators is the downloading of software. It is usually very simple to do and the most commonly used methods are covered in this section.
Getting Software Using Web-Based FTP
There are numerous Web sites that provide links to software you can download. The methodology to get the software is usually the same for all:
- Browse the desired Web site until you find the link to the software package you need.
- Click on the link for the desired software package.
- Save the file to your hard drive
Some web browsers, such as Firefox, will automatically download the file to your desktop, but where is the desktop? In Linux, your desktop is usually a sub-directory named Desktop located in your home or ~ directory. Here we see that the root user's desktop already contains a downloaded RPM file.
[root@bigboy tmp]# cd ~/Desktop/
[root@bigboy Desktop]# ls ElectricFence-2.2.2-20.2.i386.rpm
[root@bigboy Desktop]# pwd /root/Desktop
[root@bigboy Desktop]#
Getting RPMs Using Command-Line Anonymous FTP
The Web based method above transparently uses anonymous File Transfer Protocol (FTP). Anonymous FTP allows you to log in and download files from a FTP server using the username anonymous or the shorter username ftp and a password that matches your e-mail address. This way anyone can access the data. Let's illustrate this with an example of using anonymous FTP to download the SSH package from download.fedora.redhat.com:
1) First we issue the FTP command targeting download.fedora.redhat.com at the command line.
[root@bigboy tmp]# ftp download.fedora.redhat.com
Trying 66.187.232.35...
Connected to download.fedora.redhat.com (66.187.232.35). 220 Fedora FTP server ready. All transfers are logged.
Name (download.fedora.redhat.com:root): anonymous 331
Please specify the password. Password: 230 Login successful. Have fun.
Using binary mode to transfer files.
ftp> pwd
257 "/"
ftp> ls
227 Entering Passive Mode (66,187,232,35,57,155)
150 Here comes the directory listing.
drwxr-xr-x 3 ftp ftp 4096 Oct 29 15:59 pub
226 Directory send OK.
ftp>
2) After we've logged in, we can use the help command to see what options we have at our disposal.
The commands you'll most likely use are listed in Table 6-2:
Table 6-2 FTP Commands
| Command | Description |
|---|
| binary | Copy files in binary mode |
| cd | Change directory on the FTP server |
| dir | List the names of the files in the current remote directory |
| exit | Bye bye |
| get | Get a file from the FTP server |
| lcd | Change the directory on the local machine |
| ls | Same as dir |
| mget | Same as get, but you can use wildcards like "*" |
| mput | Same as put, but you can use wildcards like "*" |
| passive | Make the file transfer passive mode |
| put | Put a file from the local machine onto the FTP server |
| pwd | Give the directory name on the local machine |
3) By using the Web browsing feature on the Web site ahead of time, I know that the Fedora Core 2 RPMs are located in the pub/fedora/linux/core/2/i386/os/Fedora/RPMS/ directory and will use the cd command to change my directory to there. We can use the ls command to get a listing of files in this directory.
ftp> cd pub/fedora/linux/core/2/i386/os/Fedora/RPMS/
250 Directory successfully changed.
ftp> ls open*
227 Entering Passive Mode (66,187,232,35,58,3)
150 Here comes the directory listing.
...
...
-rw-r--r-- ... ... 184281 Oct 28 23:29 openssh-3.6.1p2-34.i386.rpm
...
...
226 Directory send OK.
ftp>
4) Next we get the file we need and place it in the local directory /usr/rpm. The hash command will print "#" hash signs on the screen during the download.
ftp> hash Hash mark printing on (1024 bytes/hash mark).
ftp> lcd /usr/rpm
Local directory now /usr/rpm
ftp> get openssh-3.6.1p2-34.i386.rpm
local: openssh-3.6.1p2-34.i386.rpm remote: openssh-3.6.1p2-34.i386.rpm
227 Entering Passive Mode (66,187,232,35,58,25)
150 Opening BINARY mode data connection for open ssh-3.6.1p2-34.i386.rpm (184281 bytes).
###############################################################
################################################################
####################################################
226 File send OK.
184281 bytes received in 3.41 secs (53 Kbytes/sec)
ftp>
Note: You can also use wildcards to download the RPMs you need using the mget command. You'll be prompted for each of the matching RPM files. In the next example, we just aborted this download by typing n.
ftp> mget openssh-3.6*
mget openssh-3.6.1p2-34.i386.rpm? n
ftp>
5) Finally we use the exit command to leave FTP.
ftp> exit
221 Goodbye.
root@bigboy tmp]#
Getting Software Using wget
The wget command can be used to download files quickly when you already know the URL at which the RPM is located. This is especially convenient if you are logged into your Linux box from another machine running a Web browser. You can browse the download site for the RPM you need, right click on the desired link and select copy shortcut (Windows) or Copy Link Location (Linux). After you have done this, you can then select your SSH/telnet/Linux Terminal login window and type in the command wget URL. Here is an example downloading a DHCP update from Fedora.
[root@bigboy tmp]# wget http://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/
Fedora/RPMS/dhcp-3.0pl2-6.16.i386.rpm
--17:38:36-- ftp://linux.stanford.edu/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/
RPMS/dhcp-3.0pl2-6.16.i386.rpm
=> `dhcp-3.0pl2-6.16.i386.rpm.5'
Resolving linux.stanford.edu... done.
Connecting to linux.stanford.edu[171.66.2.18]:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done. ==> PWD ... done.
==> TYPE I ... done. ==> CWD
/pub/mirrors/fedora/linux/core/2/i386/os/Fedora/RPMS ... done.
==> PASV ... done. ==> RETR dhcp-3.0pl2-6.16.i386.rpm ... done.
Length: 529,890 (unauthoritative)
100%[===============================>] 529,890 889.12K/s ETA 00:00
17:38:36 (889.12 KB/s) - `dhcp-3.0pl2-6.16.i386.rpm.5' saved [529890]
[root@bigboy tmp]#
