[mrtg] totals do not add up when graphing multiple targets

McDonald, Dan Dan.McDonald at austinenergy.com
Thu Feb 12 16:12:01 CET 2009

On Wed, 2009-02-11 at 05:19 -0800, pvh wrote:
> Hello,
> I've recently had to install MRTG on Windows with the latest ActivePerl at
> work to monitor a server.
> What I'm doing is graphing all active interfaces (as per the default
> cfgmaker configuration), and I added a totals graph which is simply
> something like that:
> 1:community at ip + 2:community at ip + 3:community at ip .. 

So, when one counter rolls over, mrtg has no way of knowing (and

> I'm working with fast ethernet interfaces (all 32 bit counters) here.

Thus rollovers are frequent.

The only way to accurately do this is to collect the three counters
separately, and use routers2.cgi (or some other similarly enlightened
front end, but there aren't any others published with this feature) and
build a stacked graph to show the actual total.

Note that that requires RRDtool as a backend

Daniel J McDonald, CCIE #2495, CISSP #78281, CNX
Austin Energy

-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 197 bytes
Desc: This is a digitally signed message part
Url : http://lists.oetiker.ch/pipermail/mrtg/attachments/20090212/81cfbeb1/attachment.bin 

More information about the mrtg mailing list