Threshold with CDEF values.

[Novak]

Hey guys, First post here.

I'm trying something that I never did in Cacti so I'm asking for help.

I'm monitoring disk space usage of my windows servers (2k12 and 2k8). The idea was to use threshold to generate alerts when a disk usage percentage get above n%.

The first problem: There is no data source, or OID, associated with "free disk space", so I used CDEF to generate information using the Total disk space and Used disk space (default information of Host MIB - Avaiable Disk Space Graph Template). (If someone need help with this, just PM me).

The second problem: First, I thought that just retrieving the free disk in MB would be necessary, but then realized that if I used percentage on disk graphics I could just generate one template to all graphics. So I used another CDEF to this task, convert free disk to percentage.

The third problem: Threshold plugin cannot use CDEF information to generate alerts, only data templates or data sources. And here is my problem, I dont have a data source associated to free disk space or percentage of free disk space. MY question is: Is there some way to make the Threshold Plugin use CDEF information OR Associate a CDEF value as a data source so I could use it in a Threshold Template?

Sorry for my bad english, hope my question is understandable.

If someone have a solution to my problem, I would be really grateful.

Cheers.

[cigamit]

You don't really need a CDEF to work with percentages and you don't need "Free Disk Space" since you have both "Total" and "Used" and can do the calculation off of that.

Create threshold using the datasource for "Used Space"

goto "Data Manipulation" and change "Data Type" to "Percentage"
now under that you will have a "Percent Datasource", set this to the datasource used for "Total"

Now it will automatically calculate the "Used" disk space for you. I generally set mine to alert if it goes over 80 (which means 80% used). See attached screenshot.

[Novak]

Thank you, Cigamit!

I was struggling for nothing, haha, I was introduced to Cacti a few weeks ago so sometimes I do this kind of thing.

Again, thank you very much.