[hobbit] question about "unknown DS name 'PrinterTonerCartrid'"

[Richard Finegold]

On Tue, Mar 2, 2010 at 07:34, McGraw, Robert P <rmcgraw at purdue.edu> wrote:
> I deciced to change my status line from
>        Printer Cartridge Counter = $SNMPTONERCOUNTER
> to
>        Printer Toner Cartridge Counter = $SNMPTONERCOUNTER
> and started getting the dreaded error "unknown DS name 'PrinterTonerCartrid'
> Q1) Is is possible to dump the file edit the name from 'PrinterCartridgeCo' to 'PrinterTonerCartrid' and the restore?

Yes, try a "man rrdrestore". You'd do an rrdtool dump, then edit the
XML file, then rrdtool restore. At least, that's how it's documented.

> My status line look as follows:
>       LINE="status $TARGETHOST.Prn $COLOR `date`
>
>        Printer Counter = $SNMPPAGECOUNTER
>        Printer Cartridge Counter = $SNMPTONERCOUNTER
>        Total Pages Printed Since $SINCE When We Started Counting = $PAGESPRINTED
>        Delta Pages Printed = $DELTAPAGESPRINTED
> "
> All I want to plot is the Delta Pages Printer = line.
>
> Q2) Is there a way to tell rrd to ignore other lines that I added to the status?

And here I thought you also wanted the Printer [Toner] Cartridge
Counter too. If it's only the one value, you could use:
NCV_Prn="DeltaPagesPrinter:GAUGE,*:NONE"

but that's only if the RRD file doesn't already have them. You could
erase/rename your RRD and start anew, or you can try to split it
somehow. There's probably a utility for isolating DSs from an RRD, but
that's better asked in an RRDTOOL forum. If you want to rename now and
attempt to split/merge later, there's definitely a utility for merging
RRD history; I've used "merge-rrd.tgz" (merged-rrd.py, 2005-04-11) for
that.

If you anticipate changing the number of values available for graphing
(or other analysis) in the future, you might consider using splitncv
instead. TEST2RRD is unchanged, but NCV_Prn becomes SPLITNCV_Prn:
SPLITNCV_Prn="DeltaPagesPrinter:GAUGE,*:NONE"