[mrtg] Re: False Alarms

[bwoodcoc]

Greetings again,

I've done a bit more testing with this scenario. On a test router config I 
set unknaszero option on all the targets which has 5 interfaces which we 
collect traffic and error graphs. I used "route add rtrIP 127.0.0.1" on the 
mrtg machine to simulate an outage. Unfortunately even with unknaszero set 
I get a blip of invalid data. It is unusual in that the text states Current 
IN/OUT values as zero. However the 14all graph shows a spike and also a 
bogus threshold alarm was generated leading me to believe something 
incorrect was input into the rrd and triggered the threshold handler. Next 
poll returns to apparent normalcy.

So this bug is inconsistent as only 2 of 5 interfaces blipped. It is also 
consistent whether using unknaszero or not. Any ideas whether this has been 
fixed in a later release?

Hmm, maybe I'll keyword seach on "spike" as I seem to recall that topic 
coming up.

cheers,
woody...
.
At 11:46 AM 10/2/2002 -0400, bwoodcoc wrote:

>Hello,
>
>We had an occurrence yesterday which, after post evaluation, indicates mrtg
>did not handle threshold alarms as I would have hoped. I searched the
>archives but did not find a reference to this issue so please forgive if I
>missed it.
>
>When a router becomes unavailable, the first poll thereafter I receive
>utilization and/or congestion error alarms on all (or many) of it's
>interfaces. In fact the values are more often then not unrealistic upon
>close inspection of the speed. On the second poll they clear (unless
>connectivity is flapping). Bug?? In our case we have a site with several
>routers behind a firewall which became unavailable. The barrage of mrtg
>alarms for a flapping site confused us to no end. In fact it led us astray,
>a bit of a sin in my book so hopefully there is a fix/option of some sort.
>
>Are there any options which could be set? UnKnAsZero was a thought. But
>what would happen if we had a *real* utilization/congestion issue causing
>intermittent connectivity? Would this option force an alarm clear when we
>actually would want to see the condition?
>
>I'm running 2.9.17 with rrd.
>
>Thanks in advance for your inputs.
>
>cheers,
>woody...
>
>--
>Unsubscribe mailto:mrtg-request at list.ee.ethz.ch?subject=unsubscribe
>Archive     http://www.ee.ethz.ch/~slist/mrtg
>FAQ         http://faq.mrtg.org    Homepage     http://www.mrtg.org
>WebAdmin    http://www.ee.ethz.ch/~slist/lsg2.cgi

--
Unsubscribe mailto:mrtg-request at list.ee.ethz.ch?subject=unsubscribe
Archive     http://www.ee.ethz.ch/~slist/mrtg
FAQ         http://faq.mrtg.org    Homepage     http://www.mrtg.org
WebAdmin    http://www.ee.ethz.ch/~slist/lsg2.cgi