[olug] Network performance analysis

Jason N dashrender at cox.net
Thu Nov 20 14:39:19 CST 2014


Pausing when you click a link sounds like maybe a web filtering firewall/appliance.  If the upstream device is doing scanning, etc this is pretty common.


---- Bill Brush <bbrush at gmail.com> wrote: 
Rob I'm painfully (agonizingly) aware of how many variables I'm
dealing with here.

To go into a little more detail, the raw speed seems fine for the most
part.  We're seeing some traffic spikes on the internet link up to the
limit, but it's rarely sustained.  A speed test at speedtest.net
usually comes back at around 90% of our nominal speed for our link.

The main "symptom" seems to be a lag in things starting to move.  So
if you click a link it sits there and thinks about it, then moves.
Sometimes this is a few seconds, sometimes it's over a minute.

I'm going to set up a 30 day trial of Solarwinds bandwidth analysis
pack and hopefully it will show me something.  My forays with
Wireshark have not turned up anything obvious.


On Thu, Nov 20, 2014 at 2:22 PM, Rob Townley <rob.townley at gmail.com> wrote:
> Bill,
>
> i feel your pain.
>
> Keep in mind "slowness" can be caused at many layers of the network.
>
> -physical tests to verify Cat6 compliance from (PC) patch cable to wall
> plate thru cable run back to patch panel thru another patch cable ( network
> switch).  This could be an electrician with a ~$2500.00? Cat6 tester.  $per
> wall plate
>
> -firmware on NIC / motherboard
>
> -device driver version
>
> -10Mbps half-duplex vs 1000Mbps FullDuplex
>
> -switch
>
> -vPro / IPMI
>
> -IPv6 vs IPv4 issues
>
> -DNS slowness or timing out
>
> -router
>
> -wireless channel (1 ,6, 11)
> On Nov 20, 2014 12:20 PM, "Bill Brush" <bbrush at gmail.com> wrote:
>
>> Hello all.
>>
>> I don't post much, but I've been lurking around here for many years.
>>
>> I'm looking for help investigating complaints that our network is
>> "slow".  I have a rudimentary knowledge of doing packet captures, and
>> the basics, but an in-depth investigation is beyond my current skills.
>>
>> I inherited this network a couple years ago, and I will freely admit
>> that prior to this I had never had to worry about my infrastructure so
>> I have not checked for pre-existing issues.
>>
>> So is anyone in the Omaha area an expert at network analysis?  If it's
>> your day job we can discuss your hourly rates.
>>
>> Thanks!
>> Bill
>> _______________________________________________
>> OLUG mailing list
>> OLUG at olug.org
>> https://lists.olug.org/mailman/listinfo/olug
>>
> _______________________________________________
> OLUG mailing list
> OLUG at olug.org
> https://lists.olug.org/mailman/listinfo/olug
_______________________________________________
OLUG mailing list
OLUG at olug.org
https://lists.olug.org/mailman/listinfo/olug


More information about the OLUG mailing list