Network statistics not displayed
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#5 Network statistics not displayed
Hi. I am using nmon on linux 6.5. In network statistics the transmitted bandwidth alone is not being displayed. It shows zero even though there is significant amount of traffic. I saw there was bug fix for a similar problem like this, for AIX. Is there any fix for linux too or is there some other problem?
(I am a beginner so please don't be hesitant to be elaborate)
Thanks
Hi, nmon for AIX is completely different code to the nmon for Linux so there is not similar fix. In fact I don't recall network problems for AIX for many years so that might be very old information.
You need to supply specifics:
a) Linux 6.5 - do you mean Red Hat Enterprise 6.5 or Centos 6.5 ?
b) Are you using a x86 machine (like Intel or AMD processor)?
c) Which nmon version are you using? Its at the top left when you run nmon on the screen.
d) can you capture some nmon data and attach it here? nmon -fT -s2 -c 30
Then wait two minutes and it will make a hostname_date_time.nmon file in your local directory. This file would greatly help with diagnosing your problem.
Cheers, Nigel Griffiths
Hi.. The answers to your questions :
a) red hat 6.5
b) Intel x86_64
c) nmon-14f
d) sorry I cannot attach the nmon file due to proprietary information. But i have attached the screen capture.
I have also attached a screenshot of an analyzed nmon file and highlighted the columns where I have created some traffic but still the values are zero. (I made sure that there is some traffic in that interface by taking a trace.) This issue occurs only for transmitted KB/s. As you can see in the screenshot only one interface shows the write value. The rest are not showing.
Hope this will be helpful in analyzing the issue.
Thank you so much
Sara
Thanks for the version information - looks good.
The screenshot is pointless as a bunch of zero with some columns missing and you removed even the eth number in the top line means there is no content.
Can you run?
cat /proc/net/dev >save1
sleep 10
cat /proc/net/dev >save2
and attach them? There is no secret data in the output - just a bunch of numbers.
This is where nmon is getting the data - it that has the data and the network names are sane (letters and numbers and not punctuation etc.) then its definitely a bug and I can fake similar data for testing.
Perhaps you have so many networks nmon does not cope!
Or perhaps the raw numbers are too large to handle and we need to tweak how nmon stores then and does maths.
Hi
I have attached the files that you asked for. Even this file does not have
the values. Now its clear to me why nmon displayed no values. I guess Its
not an issue with nmon. Sorry. If its not too much do you have an idea as
to why even this file displays no values?
On Fri, Jul 10, 2015 at 6:01 PM, Nigel Griffiths nigelgriffiths@users.sf.net wrote:
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#5Looking at the data
lo = loopback and eth0 to eth5, eth7 and eth8 plus bond2 and bond3 are receiving lots of data
But
- eth6 did nothing data in this 10 seconds but done a little in the past
- eth9 and bond0 did nothing and are probably not configured
On the transmit side very little is happening (except loopback (lo) but that has to match the receive loopback. Literally a handful of packets in some cases.
I have no ideas why transmit is extremely low.
- could be its not receiving data
- could be a stats reporting bug
- could be a overrun bug where the numbers are too large to hold in the data type
I would raise a problem with Red Hat support as soon as possible.
I note: that RHEL 6.5 came out November 2013 and 6.6 a year later.
Have you updated the OS since then - you may be running older software that has already been fixed.
Red Hat should advice you.
Cheers, Nigel
Hi
Thank you for your reply. I will follow it up with red hat as you advised..
Thank you.
On Mon, Jul 13, 2015 at 9:38 PM, Nigel Griffiths nigelgriffiths@users.sf.net wrote:
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Support Requests:
#5