Two important things to remember. First -- ifInOctets (and ifOutOctets) is
a counter variable -- therefore the collected value is quantified in
octets / second. Second, most links are measured in bits / second.
Therefore, to calculate %utilization on a link, there's a calculation that
must be performed:
(ifInOctets * 8 / ifSpeed) * 100
When I do this computation, I explicitly count ifInOctets and ifOutOctets
as separate entities. This is because on full-duplex links, you've got
simultaneous 2-way traffic. I've attached the MIB Expressions that I use
to collect & store in the database...
If%UtilizationOut \
"ifOutOctets / Link Speed" \
.1.3.6.1.2.1.2.2.1.16. \
8 * \
.1.3.6.1.2.1.2.2.1.5. \
/ 100 *
If%UtilizationIn \
"ifInOctets / Link Speed" \
.1.3.6.1.2.1.2.2.1.10. \
8 * \
.1.3.6.1.2.1.2.2.1.5. \
/ 100 *
--D
Duane Waddle
waddle1@us.ibm.com
"With sufficient thrust, pigs fly just fine..." -- RFC1925
"Boulieris, Arthur" <Arthur.Boulieris@NZ.UNISYS.COM>@UCSBVM.UCSB.EDU> on
01/27/2000 07:56:27 PM
Please respond to Discussion of IBM NetView and POLYCENTER Manager on
NetView <NV-L@UCSBVM.UCSB.EDU>
Sent by: Discussion of IBM NetView and POLYCENTER Manager on NetView
<NV-L@UCSBVM.UCSB.EDU>
To: NV-L@UCSBVM.UCSB.EDU
cc:
Subject: ifinoctet data format
Hello
Im running Netview 5.1.2 on solaris 2.6.
I use it for collecting ifinoctets and ifoutoctets and store the data in
oracle via RIM.
I now have a month data and am working on some end of month reports and am
puzzled by the numbers.
My calculation is add ifinoctet + ifoutoctet to get the total bandwidth
utilsation.This figure is typically around 4000.00 to 8000.00.Does anyone
know what the two decimal places are for?
Also on say a value of 8000 octets per 10 minutes(my collection interval)
the bits / sec works out to be 8000 x 8 to get total bits per 10
minutes.Then divide by 600 to get bits/sec.
This gives a value of 8000 x 8 / 600 or 106.6 bits/sec.This all seems
wrong
I expect it to be around 20 kb/s.
Am I misinterpreting the data?
I also noticed that some of the collections have a value to 8 decimal
places.Why?
If anyone out there is reporting on similar stats I would appreciate your
comments.
Regards Arthur
Arthur Boulieris
Implementation & Support
Systems Management
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