[rrd-users] gap in graph in case of UNKNOWN value

[Martin T]

I have a RRD database with a step of 60s and heartbeat of 120s. This
database holds the GAUGE value(HDD temperature of my server). There is
a script which asks temperature value from the server after every 60s
and updates the database file. Finally I have a "rrdtool graph"
script, which draws the graph. Problem is that in case the server is
not reachable to the machine where rrdtool runs and UNKNOWN value is
written to the RRD database, there is no blank gap on the graph.
Instead it looks like the temperature value is assumed to be "0". What
might cause this?

regards,
martin