Please permit calculated items!

[Crazy Marty]

For instance, my boss wants to see a single bandwidth graph with 4 different lines: the *sum* of ifInOctets for each of 2 sets of machines, and the *sum* of ifOutOctets for each of the same 2 sets of machines. He doesn't care if I have to add CPU or RAM (we have other machines that are beefy enough to do calculations on every item we collect), but he'll be really annoyed if I tell him I can't do it with Zabbix.

[nelsonab]

You can do it, but it is a hack. You'll need to set it up as a UserParameter which get's it's information from an SQL query of the Zabbix DB. Unfortunately you'll need to dig through the forums for this, I don't have the thread handy. I used it once to aggregate 4 ports together on a switch to show aggregate bandwidth.

[lamont]

For instance, my boss wants to see a single bandwidth graph with 4 different lines: the *sum* of ifInOctets for each of 2 sets of machines, and the *sum* of ifOutOctets for each of the same 2 sets of machines. He doesn't care if I have to add CPU or RAM (we have other machines that are beefy enough to do calculations on every item we collect), but he'll be really annoyed if I tell him I can't do it with Zabbix.

I can do that now with 4 different graphs by stacking lines on the graphs, but not on a single graph.

And actually I think I'd prefer to see this implemented in the graphing functionality first rather than in items. If you put it in items you're generating a whole lot more iops of sustained load on the server as the items come in and generate new derived items (which is also why i don't like the idea of creating an item that does a SQL query against the database). If you put in the graphing functionality it only gets hit when you pull the data to generate the graph, and it doesn't generate more write i/os to the disk.