[mrtg] Strange graph values

[Martin MacLeod-Brown]

Hi There everyone 
I am trying to monitor our SAN uplinks as we suspect that we have a 
bottleneck. I have set up MRTG to monitor the 4 switch ports in 
question, but I am seeing some strange results in the max and average 
bandwidth fields. 
I would expect the max data value to be constant for all the graphs 
daily, weekly, monthly yearly. Instead I have daily=96MB, weekly= 24.6 
MB monthly = 11.4MB - this can't be right??? 
Im currently sampling every minute
I am trying to use snmpv2c as they are gigabit interfaces - have I set 
this up right??? 
I have turned off scaling for all the graphs except for yearly as we 
need to pick up the spikes in bandwidth usage  and a sample section 
for my config file is below. All the monitored ports are the same 
config as the one port shown below 
# Created by 
# /usr/bin/cfgmaker xxx.xxx.xxx.xxx 
### Global Config Options 
#  for UNIX 
# WorkDir: /home/http/mrtg 
#  for Debian 
WorkDir: /var/www/mrtg 
#  or for NT 
# WorkDir: c:\mrtgdata 
### Global Defaults 
#  to get bits instead of bytes and graphs growing to the right 
 Options[_]: growright, bits 
EnableIPv6: no 
###################################################################### 
# System: xxxx 
# Description: ProCurve J8693A Switch 3500yl-48G, revision K.13.63, 
ROM K.12.17 (/sw/code/build/btm(t3a)) 
# Contact: Infrastructure_Team 
# Location: T0_Equipment_Room 
###################################################################### 
### Interface 41 >> Descr: '41' | Name: '41' | Ip: '' | Eth: '00-17- 
a4-89-a2-57' ### 
Target[xxxxxx_41]: 41:xxxx... at xxx.xxx.xx.xx:::::2 
SetEnv[xxxxxxxxx]: MRTG_INT_IP="" MRTG_INT_DESCR="41" 
MaxBytes[xxxxxxxxx]: 1250000000 
Unscaled[xxxxxxxxxx]: mwd 
Title[xxxxxxxxxxxx]: Traffic Analysis for 41 -- sst0b 
PageTop[xxxxxxxxxx1]: <h1>Traffic Analysis for 41 (ge/0) -- sst0b</h1> 
                <div id="sysdetails"> 
                        <table> 
                                <tr> 
                                        <td>System:</td> 
                                        <td>sst0b in 
T0_Equipment_Room</td> 
                                </tr> 
                                <tr> 
                                        <td>Maintainer:</td> 
                                        <td>Infrastructure_Team</td> 
                                </tr> 
                                <tr> 
                                        <td>Description:</td> 
                                        <td>41 sct0c-ge0 </td> 
                                </tr> 
                                <tr> 
                                        <td>ifType:</td> 
                                        <td>ethernetCsmacd (6)</td> 
                                </tr> 
                                <tr> 
                                        <td>ifName:</td> 
                                        <td>41</td> 
                                </tr> 
                                <tr> 
                                        <td>Max Speed:</td> 
                                        <td>125.0 MBytes/s</td> 
                                </tr> 
                        </table> 
                </div> 


Can someone help explain where I have gone wrong? 
Many Thanks 


Martin Macleod-Brown | Infrastructure Engineer - Networks & Security
Infrastructure Team
London Business School | Regent's Park | London NW1 4SA | United Kingdom
Switchboard +44 (0)20 7000 7000 | Direct line +44 (0)20 7000 7772 | Mobile +44 (0)796 690 7772 | Email mmacleod at london.edu

www.london.edu | London experience. World impact.

Please consider the environment before printing this email



______________________________________________________________________

This email has been scanned by the MessageLabs Email Security System
on behalf of the London Business School community.
For more information please visit http://www.messagelabs.com/email
______________________________________________________________________