total bandwidth wrong calculation?

dagonet · Post by **dagonet** » Sun Mar 26, 2006 5:58 am

Hi community,
we are using cacti nearly half a year. Now it seems to me, that the total bandwith is wrong calculated. I have attached to images of a webservers traffic (last day and last week).
As you can see the total out of last week is less the total out of last day.

Dagonet

Post by **gandalf** » Sun Mar 26, 2006 11:09 am

dagonet wrote:Hi community,
we are using cacti nearly half a year. Now it seems to me, that the total bandwith is wrong calculated. I have attached to images of a webservers traffic (last day and last week).
As you can see the total out of last week is less the total out of last day.

Dagonet

Arghhh, hit again. This is, how rrdtool works (if not specifically configured to work the other way round). See first few links of my signature and http://www.rrdtool.org to learn about consolidation.
To sum up: when viewing at data from last week, you're looking at consolidated data. With built-in Graph Templates, you see 6 values consolidated to one single value representing the AVERAGE of the six (AVERAGE is defined by the Graph Item). This will of course lead to numerically lower values (an AVERAGE can never be greater than each single value).
You may omit this behaviour, when adding another Graph Item for Inbound/Outbound respectively (perhaps a LINE1) that uses the consolidation function MAX(IMUM). Then you'll see that AVERAGE and MAXIMUM will give different results, but only on those Graphs using consolidated data points.
Reinhard

dagonet · Post by **dagonet** » Sun Mar 26, 2006 2:49 pm

Unfortunetly I am not that into with rrdtool. I am just using it.
But I can definitly tell, that the total in/out did work correctly, because I already used it. Now it does not work anymore.

So, I did check the total traffic per week using cacti and it did show nearly the same amount as we got from our service provider.

Dagonet

dagonet · Post by **dagonet** » Sun Mar 26, 2006 5:22 pm

After all I did some testing about the issue.
Here are the results:
When I choose "last week" from the timespan section, it shows the result like in my first posting.

When I click on the network graph to get the daily/weekly/monthly/yearly overview, it does work correctly. I do get the total amount of traffic passed from and to the specific device.

Dagonet.

dagonet · Post by **dagonet** » Tue Mar 28, 2006 3:53 pm

Hi community,
as lvm suggest I took two more screenshots to illustrate my issue.

Compare the weekly traffic graphs of web01. The Total in/out is not correct calculated in the second image.

Dagonet

Post by **gandalf** » Wed Mar 29, 2006 12:22 pm

Ok, now I understand better. The second data seems to be about 1/7 of the first one (so it may take one day only into account).
To clarify, please leave the standard Preset and manually select the start/end time from the time picker (for the same week) and post the screenshot. I suppose, that it will give the same, wron results. But this will help me to dig deeper into the code. If my assumption is correct, this will take at least until this weekend
Reinhard

dagonet · Post by **dagonet** » Wed Mar 29, 2006 12:57 pm

Here's the requested image, Reinhard.

Post by **gandalf** » Wed Mar 29, 2006 1:07 pm

Same data, as I expected. So I've to do some code inspection. This will last 'til sunday at least
Reinhard

dagonet · Post by **dagonet** » Thu Mar 30, 2006 12:30 pm

thanks for checking!
I would do it myself, but it is a very complex project.

Dagonet.

Post by **gandalf** » Sat Apr 08, 2006 2:39 pm

I just tried to reproduce.
I was comparing following graphs:
- the one obtained when clicking on the traffic graph, taking the Weekly one
- the one obtained from timeshifter, when choosing "Last Week"
both gave same results for me, when comparing the Total In/Out.
I'm using current 0.8.6h SVN code. Lately, there was some improvement/changes on the Totals Function. It is possible, that this changed sth
Reinhard

anuraganuj · Post by **anuraganuj** » Sun Apr 09, 2006 6:11 am

convert bytes to bits from cdef function

Post by **gandalf** » Sun Apr 09, 2006 7:03 am

anuraganuj wrote:convert bytes to bits from cdef function

I wonder whether this is the correct explanation. Cause this should apply to all pictures. And there are two different displays of the same week giving different results.
Reinhard

Post by **gandalf** » Mon Apr 10, 2006 3:25 pm

Please find attached my views generated with current cacti 0.8.6h (from svn). I can't find any deviation between the weekly graph produced when using the timeshifter compared to the view when displaying all 4 rras. Find my graphs attached
Reinhard

dagonet · Post by **dagonet** » Tue Apr 11, 2006 7:58 am

Hi Reinhard,
so I am going to check the SVN version and see what happens:)
Thanks for your effort!

Dagonet.

dagonet · Post by **dagonet** » Sat Apr 22, 2006 9:24 am

Hi Community, hi lvm!

my problem is solved. But I have no clue why it's working now. I did update my plugins and now it works as excepted.

Dagonet.

Cacti

total bandwidth wrong calculation?

total bandwidth wrong calculation?

Re: total bandwidth wrong calculation?

need to convert bytes to bits

Re: need to convert bytes to bits

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