[rrd-users] Concatenate 2 RRD without overlap or sum

[Simon Hobson]

On 20 Mar 2015, at 15:45, topgunx1 <topgunx1 at hotmail.com> wrote:

> I should draw a graphic with the values (IN/OUT) of 2 NICs.
> I wouldn't like that graphs overlap or sum 
> I need to placed RX1 above the RX2 (starting from Y-0),
> and TX1 above TX2 (newly starting from Y-0).

You mean, at some point T you switched things round, and you want the graph to switch around as well ?

Without going and looking stuff up (really busy right now), it's similar to the "I started a new RRD at time T and want to use the old one up to that point.

I used something like :
CDEF:aa=a,unkn,timestamp,t,lt,if
CDEF:bb=b,unkn,timestamp,t,lt,if
CDEF:cc=b,unkn,timestamp,t,ge,if
CDEF:dd=a,unkn,timestamp,t,ge,if

Then plot aa, bb:stack, cc, dd:stack
For where I've put "timestamp", you'll need to check the docs, there's a function which returns "the timestamp of the value being processed".