[Xymon] [xymon]repair rrd data

[Ralph M]

Gaps like that happen when there's missing data.  There's not a lot you can
do about that.

If you really, really want to make the gaps go away, you can try dumping
out the RRD to XML, edit the dump, then load it back in.

     rrdtool   dump   xymon.rrd

After getting past the header, you'll see the actual data in this form:

         <!-- 2024-06-19 18:55:00 EDT / 1718837700 -->
<row><v>4.0000000000e+00</v><v>3.0000000000e+01</v></row>
         <!-- 2024-06-19 19:00:00 EDT / 1718838000 -->
<row><v>4.0000000000e+00</v><v>3.0000000000e+01</v></row>
         <!-- 2024-06-19 19:05:00 EDT / 1718838300 -->
<row><v>4.0000000000e+00</v><v>3.0000000000e+01</v></row>
         <!-- 2024-06-19 19:10:00 EDT / 1718838600 -->
<row><v>4.0000000000e+00</v><v>3.0000000000e+01</v></row>
         <!-- 2024-06-19 19:15:00 EDT / 1718838900 -->
<row><v>4.0000000000e+00</v><v>3.0000000000e+01</v></row>

I think where there's a missing value, you'll see "NaN" or something
similar.  You could rewrite the empty values with an average of the row
above and below.  After saving the file, import it back into a new RRD.
The problem with doing all that is you have to get it done between samples
being written, which is typically 5 minute intervals.  If you don't swap
the old RRD for the new one in time, you'll miss the next sample.

Ralph Mitchell



On Thu, Jun 20, 2024 at 11:16 AM <diffusion at bulot-fr.com> wrote:

> Hello
>
> I have many ncv graph and they often "dotted" instead made of lines
> It's like some data left in rrd : see attachment
>
> * How to correct without loosing all data ?
> * how it's happened ?
>
> I had search for "rrd repair tools" but nothing seems works on my
> server or PEBCAK ;-)
>
> (hope my english is not too bad)
>
> _______________________________________________
> Xymon mailing list
> Xymon at xymon.com
> http://lists.xymon.com/mailman/listinfo/xymon
>
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