calculate link availability via MYLINK_BANDWIDTH.rrd file

[zaji_nms]

dear Expert

some of our main links, if they are UP, always having traffic, (if DOWN , no traffic), in this case we can calculate the availability of the link if we come to know what time Mylink_Bandwidth.rrd having 0 value

once again above
if there is absolute zero value on 5 minutes time slot (ds0 or ds1)

rrdtool graph dummy -s20190101 -e20190201 DEF:test=Mylink_Bandwidth.rrd:1:_______________ <<<< some formula need to be require with if condition to calculate number of slots (if value=0) then multiply by 5 (or total time when there is 0 value)

regards

[tgriep]

The rrdgraph_rpn has information on formulas that may work for you to do some calculations on the RRD data. See below.
https://oss.oetiker.ch/rrdtool/doc/rrdgraph_rpn.en.html