Switch interface shows more bandwidth used than server

This support forum board is for support questions relating to Nagios Network Analyzer, our network traffic and bandwidth analysis solution.
Locked
awilson
Posts: 224
Joined: Mon Mar 21, 2016 1:20 pm

Switch interface shows more bandwidth used than server

Post by awilson »

Hi. NNA is showing the bandwidth used for a switch interface to be significantly higher than the server interface attached to the switch. The switch bandwidth is approximately twice the transmit and receive values combined seen from the server interface.

The server is a VM running Redhat 7. We used iftop to determine the bandwidth used.

Is this something that would be normal?

Thanks.
awilson
Posts: 224
Joined: Mon Mar 21, 2016 1:20 pm

Re: Switch interface shows more bandwidth used than server

Post by awilson »

Clarification: We are monitoring the switch WAN interface with NNA and selecting the source host IP to determine the bandwidth used.

Thanks
User avatar
tgriep
Madmin
Posts: 9177
Joined: Thu Oct 30, 2014 9:02 am

Re: Switch interface shows more bandwidth used than server

Post by tgriep »

I cannot comment on how the iftop command calculates the bandwidth data.

One thing to note is when looking at the bandwidth graph on the NNA server. it is displaying the traffic for the last 5 minutes by default.

Also, it you run a query, on the NNA server, the time frame may be a bit larger than the time frame that is selected as the data is calculated when the data flow started or ended and that could fall out of the selected time of the query.
Be sure to check out our Knowledgebase for helpful articles and solutions!
awilson
Posts: 224
Joined: Mon Mar 21, 2016 1:20 pm

Re: Switch interface shows more bandwidth used than server

Post by awilson »

Thanks

You can close
scottwilkerson
DevOps Engineer
Posts: 19396
Joined: Tue Nov 15, 2011 3:11 pm
Location: Nagios Enterprises
Contact:

Re: Switch interface shows more bandwidth used than server

Post by scottwilkerson »

awilson wrote:Thanks

You can close
Great!

Locking
Former Nagios employee
Creator:
ahumandesign.com
enneagrams.com
Locked