I can't start the collector, it complains about a library missing!

The error message might look something like this:

bash-2.03# collector -V
collector: error in loading shared libraries: libmysqlclient.so.6:
cannot open shared object file: no such file or directory
					 

First of all, check if you even have MySQL installed on your machine. Second, check whether you hav a file call libmysqlclient.so.6. If you only have a ".5", your version is too old, if it's ".7", it's too new (I guess it doesn't even exist at the moment ... just preparing ... :-) ). Once you find it, check the file "/etc/ld.so.conf" for the directory you found the library in. Most likely it will not be in there. Add the directory name, and run "ldconfig -X" as root. This should force the machine to rebuild the list of libraries, and should allow collector to be run.

I've got everything set up, but no data gets collected ...

Two possibilities ... one, for the regular cronjob, do not use the "-c"-option. This is only used after changing router configs, or adding new hosts to the system. Two, only ports with customer assignment are accounted.

No data gets collected from my Novell-server ...
Only some of my router's/switch's ports are created by collector...

As an improvement over the old program, PACT relies on unique port names. This is extremely helpfull on systems like Ciscos and the like. Changing certain configs on a Cisco (e.g. adding extra timeslots on a Fractional T1) tends to change the sequence number of the interfaces, creating a total mess when only using them. Anyway, all the systems I've had available assigned unique names to all ports.
Novell doesn't. So, when the system scans through the list of interfaces, it gets confused. This problem was present in all versions up to 0.6, and is corrected in the 0.7 version.
The same behaviour has been noticed on Catalyst 4000 switches. Switching to the "Novell"-mode in the host usually corrects this.

I have entered (n>3) hosts into the table, but all collector does is get the data from the first three!

As documented in the README included in the program archive, collector has been limited to three hosts in the freely downloadable version. Non-profit organizations can request free licences, for commercial uses there are three different levels of PACT available: 5 hosts ("SOHO"), 25 hosts (medium) and unlimited hosts. Please contact me for further information.

The pages complain about not being able to find "global.php3"!

Check the manual ... the PACT-archive contains a file called "global.php3-dist" ... edit to suit your setup, and save as "global.php3".

I've corrected my system clock, and now I've got some huge values in the database!

Known bug ... present in collector up to 0.7, fixed in 0.8.

What's the deal with the MySQL-license?

MySQL is used as the database to store all the data - customers, hosts, ports, as well as the accounting data itself. MySQL is - IMHO - one of the best databases for small to medium use available for Linux, and one of the cheapest, too! As far as I know, a commercial license runs $200 at the moment, and is not limited in the number of concurrent users. For non-commercial use (and even commercial use when you do your own programming) the license is free! And even the source is availabe! As performance was one of the main design goals, it outperforms most commercial databases (tested it myself against Informix SE; also they have extensive benchmarks ...).
A license has to be bought when you purchase a software product that relies exclusively on MySQL (which currently is the case with PACT). If you already own a commercial license of MySQL for the same machine you plan to use as a DB-server for PACT, you will not need an extra license. For non-commercial licenses, licensing MySQL is not required.