My view on this is:
- I prefer PostgresQL - it's a more mature database.
- I prefer Apache2
- I prefer PHP5 - I hate this language and think it has tendency to push poor programmers to shoot themselves (and their users) in their feet but if I have to install it on my machine then I'd rather use the latest and greatest.
- I prefer mod-php5 as opposed to the other ways to integrate Apache2 with PHP.
In addition, the Debian packages state their dependencies in a way that seems to encourage Aptitude to choose Apache (1), MySQL and PHP4.
So first thing first: After picking gallery2 for installation in Aptitude, go through all the packages it depends on and remove the ones you don't want and which have other alternatives. Get rid of the PHP4 and MySQL dependencies - Aptitude makes it pretty easy by simply making sure that you choose other packages to satisfy the dependencies and remove the rest. Just follow the suggestions made by Aptitude when you ask to remove a package with dependencies on it, and make sure that Aptitude doesn't signal "Broken Packages" before going ahead to execute the changes.
Setup a separate user for gallery:
$ sudo adduser --system --group gallery
Does the trick - add a system user (with a shell of /bin/false), create a home directory for it and a group especially for it.
The following should be pretty self-explanatory but the summary is: Create a new role ("user"), create a database, set a password, allow role to be logged in:
$ sudo -u postgres psql
postgres=# create role gallery;
postgres=# create database gallery owner gallery;
postgres=# alter role gallery encrypted password 'password';
postgres=# alter role gallery login;
Allow logging in to role "gallery" from another user without having to run psql as the UNIX user "gallery" by adding the following lines to the end of /etc/postgresql/8.1/main/pg_hba.conf:
local gallery gallery md5
And I also had to enable access to Gallery2's index.php by adding "Indexes" to the Options line in /etc/apache2/conf.d/gallery2 (link to /etc/gallery2/apache.conf
After that I could access my web server's "/photos/" and start the automatic configuration.