<p>Hi All,</p>
<p>I'm getting to grips with RRD tool for the first time, but I'm running in to problems getting even a simple example working.</p>
<p>The problem: </p>
<p>I have a historical set of data (bytes received per minute) that I wish to "preload" in to an RRDB <br>before providing regular (per minute) updates going forward. I'm using rrdtool 1.2.15 on Cygwin. My datasource has<br>
periodic gaps - I'm presuming these gaps will automatically be marked as unknown.</p>
<p>C:/cygwin/bin/rrdtool.exe create c:/logmunge.dbt.pacs.com/rrd_db/RC1DBWF01.rrd --start 1199967600 --step 60 DS:bytes:ABSOLUTE:600:U:U RRA:LAST:0.5:1:600</p>
<p>How I interpret this: "Create a new RRD database storing times from Thu, 10 Jan 2008 12:20:00 GMT.<br>Records are added every 60 seconds. There is a single datasource called "bytes", consisting of a ABSOLUTE datasource,<br>
that is each record is counted from 0, and is not dependant on the last. If no data is received in 600 seconds, mark it as "unknown". <br>Create 1 round robin archive, consisting of the LAST value (As we guarantee only a single update in a minute), and xff of 0.5, and with PDP<br>
calculated from a single update. Store 600 rows (10hr 1min)."</p>
<p>(RRD File Created)</p>
<p>Add a single record:</p>
<p>C:/cygwin/bin/rrdtool.exe updatev c:/logmunge.dbt.pacs.com/www/../rrd_db/RC1DBWF01.rrd -t bytes "1199967601:1432694"</p>
<p>$ rrdtool.exe info ../rrd_db/RC1DBWF01.rrd<br>filename = "../rrd_db/RC1DBWF01.rrd"<br>rrd_version = "0003"<br>step = 60<br>last_update = 1199967601<br>ds[bytes].type = "ABSOLUTE"<br>ds[bytes].minimal_heartbeat = 600<br>
ds[bytes].min = NaN<br>ds[bytes].max = NaN<br>ds[bytes].last_ds = "UNKN"<br>ds[bytes].value = 1.4326940000e+06 <<< VALUE ADDED<br>ds[bytes].unknown_sec = 0<br>rra[0].cf = "LAST"<br>rra[0].rows = 600<br>
rra[0].pdp_per_row = 1<br>rra[0].xff = 5.0000000000e-01<br>rra[0].cdp_prep[0].value = NaN<br>rra[0].cdp_prep[0].unknown_datapoints = 0</p>
<p>Immediately add another record for 23 minutes later:</p>
<p>C:/cygwin/bin/rrdtool.exe update c:/logmunge.dbt.pacs.com/www/../rrd_db/RC1DBWF01.rrd -t bytes "1199968981:5990214"</p>
<p>$ rrdtool.exe info ../rrd_db/RC1DBWF01.rrd<br>filename = "../rrd_db/RC1DBWF01.rrd"<br>rrd_version = "0003"<br>step = 60<br>last_update = 1199968981<br>ds[bytes].type = "ABSOLUTE"<br>ds[bytes].minimal_heartbeat = 600<br>
ds[bytes].min = NaN<br>ds[bytes].max = NaN<br>ds[bytes].last_ds = "UNKN"<br>ds[bytes].value = NaN <<< Why is this NaN???<br>ds[bytes].unknown_sec = 1<br>rra[0].cf = "AVERAGE"<br>rra[0].rows = 600<br>
rra[0].pdp_per_row = 1<br>rra[0].xff = 5.0000000000e-01<br>rra[0].cdp_prep[0].value = NaN<br>rra[0].cdp_prep[0].unknown_datapoints = 0</p>
<p>Why is this value marked as unknown? I'm itching to generate a graph but don't seem to be able to get my head around the basics - What am I missing?</p>
<p>Any help gratefully received!</p>
<p>Kind Regards,</p>
<p>Neil Saunders.</p>