How to graph sum of multiple ISDN channels as an aggregate

[mikepont]

Hi,

I'd like to be able to sum a number of B channels on an ISDN router and graph the total input and output - for example my ISDN router dials up 4 x 64K calls for a total of 256K. I'd like to sum the input and output values of each B channel and then graph these totals to get aggregate utilisation

I guess I can do this with CDEFs

[bulek]

Hmm... depending on router model you can read these values directly from MIB. For example on cisco read statistics from Dialer interface, not from ISDN. It will report overal traffic coresponding to all ISDN interfaces used for call.

Another idea is to use STACKED graph where utilization of one B-channel is painted over another one (and maybe some others) - this way you will see total traffic.

- bulek

[mikepont]

Thanks for that -I tried the STACKED graph and it works well

[yid]

Using a STACK graph_item type will work (I'm guessing that's what you did). Alternatively (if you want to GPRINT it), you could create a CDEF to add them together.