Graph Network Usage

[Jeff Stuart]

As we all know, you can use MRTG + SNMP to graph network usage.  BUT instead 
of having to install 2 new programs + an external hobbit script that runs 
either on each box or on a centralized location, you can use this external 
script that runs on the client.

Basically it just grabs the data from the /proc/net/dev file.  Note: this 
probably only works on Linux.

Then you add the following lines to your hobbitserver.cfg:

TEST2RRD="cpu=la,disk,inode,...,hobbitd,bandwidth=ncv"
NCV_bandwidth="bytesin:COUNTER,bytesout:COUNTER"
GRAPHS="la,disk,inode,...,hobbitd,ncv,bandwidth"

Then in your hobbitgraph.cfg, add this entry:

[bandwidth]
        TITLE Network Traffic
        YAXIS Bits/Second
        DEF:inbytes=bandwidth.rrd:bytesin:AVERAGE
        CDEF:in=inbytes,8,*
        DEF:outbytes=bandwidth.rrd:bytesout:AVERAGE
        CDEF:out=outbytes,8,*
        CDEF:total=in,out,+
        VDEF:pct95=total,95,PERCENT
        LINE2:in#00FF00:Inbound
        GPRINT:in:LAST: \: %9.1lf (cur)
        GPRINT:in:MAX: \: %9.1lf (max)
        GPRINT:in:MIN: \: %9.1lf (min)
        GPRINT:in:AVERAGE: \: %9.1lf (avg)\n
        LINE2:out#FF0000:Outbound
        GPRINT:out:LAST: \: %9.1lf (cur)
        GPRINT:out:MAX: \: %9.1lf (max)
        GPRINT:out:MIN: \: %9.1lf (min)
        GPRINT:out:AVERAGE: \: %9.1lf (avg)\n
        LINE2:total#00CCCC:Total Usage
        GPRINT:total:LAST: \: %8.1lf (cur)
        GPRINT:total:MAX: \: %8.1lf (max)
        GPRINT:total:MIN: \: %8.1lf (min)
        GPRINT:total:AVERAGE: \: %9.1lf (avg)\n
        LINE1:pct95#0000FF:Outbound 95th percentile
        GPRINT:pct95:\: %6.2lf %Sbps \n

And then finally setup this script as an external script for each client:

#!/bin/sh

/bin/grep eth0 /proc/net/dev | /bin/awk '{print "bytes_in : " 
$2 "\nbytes_out : " $10}' > $BBTMP/bandwidth.txt

$BB $BBDISP "status $MACHINE.bandwidth green `date`

`cat $BBTMP/bandwidth.txt`
"

/bin/rm $BBTMP/bandwidth.txt
exit 0

Hope this helps someone!  

P.S.
	Thx Henrik for your EXCELLENT tutorial on the NCV graph stuff.  Made my job a 
1000x easier! :)  Also, in the next week, I'm gonna be blowing my boss's mind 
with some of the stuff I'll be able to track and graph.  Hehe.. there's just 
SOO MUCH you can do when you can do it on the command line vs a windows 
program that can only access stuff via SNMP/TCP/UDP probes.

-- 
Jeff Stuart
Network Admin 
MyInternetServices.com
1-800-300-HOST