TOPIC: APT
A fallback installation routine?
9th November 2007In a previous sustained spell of Linux meddling, the following installation routine was one that I encountered rather too often when RPM's didn't do what I required of them (having a SUSE distro in a world dominated by a Red Hat standard didn't make things any easier...):
tar xzvf progname.tar.gz; cd progname
The first part of the command extracts from a tarball compressed using gzip and the second one changes into the new directory created by the extraction. For files compressed with bzip use:
tar xjvf progname.tar.bz2; cd progname
The command below configures, compiles and installs the package, running the last part of the command in its own shell.
./configure; make; su -c make install
Yes, the procedure is a bit convoluted, but it would have been fine if it always worked. My experience was that the process was a far from foolproof one. For instance, an unsatisfied dependency is all that is needed to stop you in your tracks. Attempting to install a GNOME application on a KDE-based system is as good a way to encounter this result as any. Other horrid errors also played havoc with hopeful plans from time to time.
It shouldn't surprise you to find that I will be staying away from the compilation/installation business with my main Ubuntu system. Synaptic Package Manager and its satisfactory dependency resolution fulfil my needs well and there is the Update Manager too; I'll be leaving it for Canonical to do the testing and make the decisions regarding what is ready for my PC as they maintain their software repositories. My past tinkering often created a mess, and I'll be leaving that sort of experimentation for the safe confines of a virtual machine from now on...
Setting up a test web server on Ubuntu
1st November 2007Installing all the bits and pieces is painless enough so long as you know what's what; Synaptic does make it thus. Interestingly, Ubuntu's default installation is a lightweight affair with the addition of any additional components involving downloading the packages from the web. The whole process is all very well integrated and doesn't make you sweat every time you need to install additional software. In fact, it resolves any dependencies for you so that those packages can be put in place too; it lists them, you select them and Synaptic does the rest.
Returning to the job in hand, my shopping list included Apache, Perl, PHP and MySQL, the usual suspects in other words. Perl was already there, as it is on many UNIX systems, so installing the appropriate Apache module was all that was needed. PHP needed the base installation as well as the additional Apache module. MySQL needed the full treatment too, though its being split up into different pieces confounded things a little for my tired mind. Then, there were the MySQL modules for PHP to be set in place too.
The addition of Apache preceded all of these, but I have left it until now to describe its configuration, something that took longer than for the others; the installation itself was as easy as it was for the others. However, what surprised me were the differences in its configuration set up when compared with Windows. There are times when we get the same software but on different operating systems, which means that configuration files get set up differently. The first difference is that the main configuration file is called apache2.conf on Ubuntu rather than httpd.conf as on Windows. Like its Windows counterpart, Ubuntu's Apache does use subsidiary configuration files. However, there is an additional layer of configurability added courtesy of a standard feature of UNIX operating systems: symbolic links. Rather than having a single folder with the all configuration files stored therein, there are two pairs of folders, one pair for module configuration and another for site settings: mods-available/mods-enabled and sites-available/sites-enabled, respectively. In each pair, there is a folder with all the files and another containing symbolic links. It is the presence of a symbolic link for a given configuration file in the latter that activates it. I learned all this when trying to get mod_rewrite going and changing the web server folder from the default to somewhere less susceptible to wrecking during a re-installation or, heaven forbid, a destructive system crash. It's unusual, but it does work, even if it takes that little bit longer to get things sorted out when you first meet up with it.
Apart from the Apache set up and finding the right things to install, getting a test web server up and running was a fairly uneventful process. All's working well now, and I'll be taking things forward from here; making website Perl scripts compatible with their new world will be one of the next things that need to be done.