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Once in dselect, you will get this screen:
0. [A]ccess Choose the access method to use.
1. [U]pdate Update list of available packages, if possible.
2 [S]elect Request which packages you want on your system.
3. [I]nstall Install and upgrade wanted packages.
4. [C]onfig Configure any packages that are unconfigured.
5. [R]emove Remove unwanted software.
6. [Q]uit Quit dselect.
Let’s look at these one by one.
The Access screen is shown in Figure 3.2 on page 86.
Here we tell dselect where our packages are. Ignore the order that these appear in. It is very important that you select the proper method for installation. You may have a few more methods listed, or a few less, or you may see them listed in a different order; just don’t worry about it. In the following list, we describe the different methods.
Confirmation that you are using a multi-cd set
The location of the Debian distribution on the disk(s)
[ Possibly ] the location(s) of the Packages file(s)
Once you have updated the available list and selected the packages to be installed, the multi_cd method diverges from normal procedure. You will need to run an “install” step for each of the CDs you have, in turn. Unfortunately, due to the limitations of dselect, it will not be able to prompt you for a new disk at each stage; the way to work for each disk is outlined here:
It may be necessary to run the installation step more than once to cover the order of package installation; some packages installed early may need to have later packages installed before they will configure properly.
Running a “Configure” step is recommended to help fix any packages that may end up in this state.
These are similar to the multi_cd method and are refinements on the theme of coping with changing media – for example, installing from a multi_cd set exported via NFS from another machine’s CD-ROM drive. indexdselect!multi-NFS, multi-mount installation
Configuration of this method is straightforward. You may select any number of different locations, mixing and matching file: URLs (local disks or NFS mounted disks), http: URLs, or ftp: URLs. Note, however, that the HTTP and FTP options do not support local authenticating proxies.
If you have proxy server for either HTTP or FTP (or both), make sure you set the http_proxy and ftp_proxy environment variables, respectively. Set them from your shell before starting dselect by using the following command:
# dselect
dselect will read the Packages or Packages.gz files from the mirror and create a database on your system of all available packages. This may take a while as it downloads and processes the files.
Hang on to your hat. This is where it all happens. The object of the exercise is to select just which packages you wish to have installed.
Press Enter. If you have a slow machine, be aware that the screen will clear and can remain blank for 15 seconds. So don’t start bashing keys at this point.
The first thing that comes up on the screen is page 1 of the Help file. You can get to this help by pressing ? at any point in the “Select” screens, and you can page through the help screens by hitting the . (full stop) key.
Before you dive in, note these points:
Let’s look at the top two lines of the Select screen. This header reminds us of some of the special keys listed in Table 3.1.
Table 3.2 lists the states that dselect uses to denote the status of each package it is aware of.
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Rather than spell all this out here, I refer you to the Help screens where all is revealed. One example, though.
You enter dselect and find a line like this:
** Opt misc loadlin a loader (running under DOS) for LINUX
This is saying that loadlin was selected when you last ran dselect and that it is still selected, but it is not installed. Why not? The answer must be that the loadlin package is not physically available. It is missing from your mirror.
The information that dselect uses to get all the right packages installed is buried in the packages themselves. Nothing in this world is perfect, and it does sometimes happen that the dependencies built into a package are incorrect, which means that dselect simply cannot resolve the situation. A way out is provided where the user can regain control; it takes the form of the commands Q and X, which are available in the Select screen.
Select screen (dselect) Keys that help you not to get lost (!) are R, U, and D.
An example follows. The boot-floppies package (not an example for beginners, I know, but it was chosen because it has a lot of dependencies) depends on these packages:
The person maintaining boot-floppies also thinks that the following packages should be installed. These are not, however, essential:
When you select boot-floppies, dselect brings up the conflict resolution screen. You’ll notice that all the required packages have been selected.
Pressing the R key puts things back to the starting point.
EIOM Pri Section Package Description
__ Opt admin boot-floppie Scripts to create the Debian
__ Opt devel newt0.25-dev Developer’s toolkit for newt
__ Opt devel slang1-dev The S-Lang programming library
__ Opt devel slang1-pic The S-Lang programming library
If you decide now that you don’t want boot-floppies, just press Enter.
Pressing the D key puts things the way I selected them in the first place:
_* Opt admin boot-floppie Scripts to create the Debian
__ Opt devel newt0.25-dev Developer’s toolkit for newt
__ Opt devel slang1-dev The S-Lang programming library
__ Opt devel slang1-pic The S-Lang programming library
Pressing the U key restores dselect’s selections:
EIOM Pri Section Package Description
_* Opt admin boot-floppie Scripts to create the Debian installation
_* Opt devel newt0.25-dev Developer’s toolkit for newt
_* Opt devel slang1-dev The S-Lang programming library
_* Opt devel slang1-pic The S-Lang programming library
I suggest running with the defaults for now; you will have ample opportunities to add more later.
Whatever you decide, press Enter to accept and return to the main screen. If this results in unresolved problems, you will be bounced right back to another problem resolution screen.
The R, U, and D keys are very useful in “what if” situations. You can experiment at will and then restore everything and start again. Don’t look on them as being in a glass box labeled “Break in Case of Emergency.”
After making your selections in the Select screen, press I to give you a big window, press t to take you to the beginning, and then use the Page Down key to look quickly through the settings. This way you can check the results of your work and spot glaring errors. Some people have deselected whole groups of packages by mistake and not noticed the error until too late. dselect is a very powerful tool; don’t misuse it.
You should now have the situation shown in Table 3.3.
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Happy? Press Enter to exit the Select process. You can come back and run Select again if you wish.
dselect runs through the entire set of packages and installs those selected. Expect to be asked to make decisions as you go. It is often useful to switch to a different shell to compare, say, an old configuration with a new one. If the old file is conf.modules, the new one will be conf.modules.dpkg-dist.
The screen scrolls past fairly quickly on a fast machine. You can stop and start it with Ctrl-s and Ctrl-q, respectively, and at the end of the run, you will get a list of any uninstalled packages.
It can happen that a package does not get installed because it depends on some other package that is listed for installation but is not yet installed. The answer here is to run Install again. Cases have been reported where it was necessary to run it four times before everything slipped into place. This will vary by your acquisition method.
Most packages get configured in step 3, but anything left hanging can be configured here.
Removes packages that are installed but no longer required.
I suggest running /etc/cron.daily/find at this point, because you have a lot of new files on your system. Then you can use locate to get the location of any given file.
