[rrd-users] RRD Graphs on the fly?

[Simon Hobson]

John Nicastro wrote:

>Hello, new to RRD so bare with me. WOuld like to do the following, 
>please let me know if possible and point to a "how-to" if it exists:
>
>1) ONLY WHEN USER INITIATES, Import data from Oracle table holding 
>samples (5 min based), convert into RRD
>2) Create on-the-fly graphs from this data for the user
>
>So, we have a PERL cgi. User selects a router from a list, query is 
>sent to Oracle to grab data for this router for the last 4 hours 
>(this part is done). I need to know what my next steps are to 
>properly convert this data into RRD format and then graph the data. 
>All this on the fly from a web based form.


The steps you need to take are fairly simple :

1) extract the data - you've already got that covered

2) create/recreate the rrd database

3) draw graphs

Step 2 can be done either by creating an empty database and 
performing a number of updates to insert the data. Alternatively I 
believe there is the capability to import an XML file.

Step 3 is no different to a 'normal' setup where data is collected 
and inserted over time. Just generate the required graphing commands 
and either call the rrdtool graph command, or use something like the 
Perl module.


There are documentation pages on the RRD website.