Choosing the best data input method

[Entity]

Hi all,

I've got a small perl script which queries a mysql db for user count on our irc servers.
The output of the script is flexible:
a) servername:usercount
b) servername1:usercount1 servername2:usercount2 ....

I'm still learning the ropes in Cacti, so my question is which data input method is the best when I want to achieve the following:
- roughly 20 servers to monitor
- each server in its own graph
- one graph with the sum of all servers
- minimize sql queries
- flexible system to add new servers / delete old ones

I read the docu about the data input method and a basic setup is working fine. I couldnt quite figure out the "Script query" and "Script server" concept with respect to my task. Is there a better method than to run the same script 20 times (output version a) for all the different servers?

Thanks for an input or guide,

Entity

[rony]

I would write you script so that you can use it with Data Queries. This will allow for easy single graph creation. Concerning totals, well 2 routes for that, you can have your script present to total as a "host" or index value, or you can manually create and maintain the total graph. I suggest that you have the script do it.

For an example of data query and output and function, check out the "unix host disk" one.

[Entity]

Thanks for the input rony.
I tried to understand the data query for "Unix - Get Mounted Partitions". I have to admint I didn't understand it
Trying to make it work from my localhost device is the first thing I didn't manage. Cacti tells me the following:

In Management -> Devices:
2) Unix - Get Mounted Partitions Success [0 Items, 0 Rows]

In New Graphs:
This data query returned 0 rows, perhaps there was a problem executing this data query. You can run this data query in debug mode to get more information.

The verbose mode shows this:
+ Running data query [6].
+ Found type = '4 '[script query].
+ Found data query XML file at '/home/mindpage/cacti/resource/script_queries/unix_disk.xml'
+ XML file parsed ok.
+ Executing script for list of indexes 'perl /home/mindpage/cacti/scripts/query_unix_partitions.pl index'
+ Executing script query 'perl /home/mindpage/cacti/scripts/query_unix_partitions.pl query device'
+ Executing script query 'perl /home/mindpage/cacti/scripts/query_unix_partitions.pl query mount'
+ Found data query XML file at '/home/mindpage/cacti/resource/script_queries/unix_disk.xml'
+ Found data query XML file at '/home/mindpage/cacti/resource/script_queries/unix_disk.xml'
+ Found data query XML file at '/home/mindpage/cacti/resource/script_queries/unix_disk.xml'

When I execute the scripts manually I get:
# perl /home/mindpage/cacti/scripts/query_unix_partitions.pl index
/dev/hda2
# perl /home/mindpage/cacti/scripts/query_unix_partitions.pl query device
/dev/hda2:/dev/hda2
# perl /home/mindpage/cacti/scripts/query_unix_partitions.pl query mount
/dev/hda2:/

Hope you can help me a bit to get the whole thing running. Thanks in advance.

Edit:
Running Cacti 0.86g with all patches applied and also exchanged the scripts from here: http://forums.cacti.net/viewtopic.php?t=9352