Can i know the total bandwith of my architecture?

[Acid]

Hi !

I would like to know if Cacti can do substraction ?
I explain :

All my servers are connected on a switch (unmanaged).
On the swith, there's many servers (not only the servers on the graph in attachment).

On this switch, i'd would like to know the real outbound of the servers behind.

This can be resume in a simple equation :

Total Outbound = (Outbound Front1 + Outbound Front2) - Inbound DB1
Total Inbound = Inbound LoadBal1 + ((Inbound Front1 + Inbound Front2) - Outbound Loadbal1 - Outbound DB1)

Is there a solution to do it ?

And, if the switch is managed ? How can i do this ?

I 've seen a plugin able to aggregate graphs.
It's a solution for me, but i need to substract ^^

Thanks a lot the community for this great work !

[Howie]

I don't know how you do this in a Cacti graph, but for what it's worth, weathermap can do subtraction of one target from another...

TARGET a.rrd -b.rrd

(make sure there's no space after the -)

[Acid]

Thanks for your answer !

Yes, i use weathermap.

I tested your solution, but i've found a problem.

If I do a graph1+graph2-graphdb, it results in a :
Total Outbound = Outbound Front1 + Outbound Front2 - Outbound DB1

BUT, I want a :
Total Outbound = (Outbound Front1 + Outbound Front2) - INBOUND DB1

(To know the real bandwith in switch->firewall, and not of the interface of the switch)

Have you an idea ?

[Howie]

You can swap over in and out for one DS...

TARGET a.rrd b.rrd -c.rrd:traffic_out:traffic_in

[Acid]

Whaou, so fast to answer ... thank you !!

It's ok for my outbound !

But now, I've the Inbound of my database in the substraction.
So the total Inbound is false.

The total inbound isn't calculate with the same servers of the outbound.
Can i parameter that ?

(i don't know the parameters of the weathermap config file)

Thanks a lot to help me

[Howie]

No problem

You can ignore either side too, like this:

TARGET a.rrd:-:traffic_in

to get a 0 in the 'in' slot, and the in value in the 'out' slot.

[Acid]

Thanks, you're a boss !

It works like a charm.

[Acid]

:s

My boss want a graph in Cacti -_-

The plugin Aggregate seems to answer my needs, but, can i do substraction with it (like above) ?

Thanks