[mrtg] Graphing Uptime

Fri Sep 28 22:36:38 CEST 2018

>>
>>uptime=`snmpwalk -v1 -c public 10.0.0.1 SysUptime | awk -F'[()]' '{print $2}'`
>>let hours=uptime
>>let hours=$hours/100/60/60
>>echo $hours
>>
>>If you run that bash and pass it into MRTG, with directives to create a gauge type
>>graph, you should get a fairly nifty uptime graph. With correct units for time as a
>>bonus.

Similar to the above script, this is what I use for plotting uptime with MRTG.
If your snmpget binary supports the "-Otv" formatting flags it should work.

#!/bin/bash
#
# uptime.sh
# make a call to snmpget with -Otv formatting to just uptime in
# timeticks only, not with x days hours etc.
#
# ./uptime.sh <read_community> <devicename_or_ip>
# ./uptime.sh public myrouter1
#
COMMUNITY=$1
HOST=$2
UPTIMETICKS=$(/usr/bin/snmpget -v2c -Otv -c $COMMUNITY $HOST .1.3.6.1.2.1.1.3.0)
#UPTIMEDAYS=$(expr $UPTIMETICKS / 8640000)
echo $UPTIMETICKS
echo $UPTIMETICKS
echo $UPTIMETICKS
echo $UPTIMETICKS
# end uptime.sh

And the MRTG target config that calls uptime.sh looks like this:

ShortLegend[myrouter_uptime]: days
YLegend[myrouter_uptime]: days
LegendI[myrouter_uptime]: days
LegendO[myrouter_uptime]: days
Directory[myrouter_uptime]: myrouter
WithPeak[myrouter_uptime]: ywm
MaxBytes[myrouter_uptime]: 100000
Options[myrouter_uptime]: growright, gauge, nopercent
Title[myrouter_uptime]: myrouter Uptime in Days
Target[myrouter_uptime]: `/opt/mrtg/bin/scripts/uptime.sh public myrouter` / 8640000
PageTop[myrouter_uptime]: <H1>myrouter Uptime in Days</H1>
  <TABLE>
    <TR><TD>ifType:</TD><TD>gauge</TD></TR>
    <TR><TD>Resource:</TD><TD><br>
    uptime.sh
    </TD></TR><br>
  </TABLE>

If you are not the intended recipient of this message (including attachments) or if you have received this message in error, immediately notify us and delete it and any attachments.

If you do not wish to receive any email messages from Edward Jones, excluding administrative communications, please email this request to Opt-Out at edwardjones.com from the email address you wish to unsubscribe.

For important additional information related to this email, visit  http://www.edwardjones.com/disclosures/email.html. Edward D. Jones & Co., L.P. d/b/a Edward Jones, 12555 Manchester Road, St. Louis, MO 63131 © Edward Jones. All rights reserved.

-----Original Message-----
From: mrtg [mailto:mrtg-bounces+greg.volk=edwardjones.com at lists.oetiker.ch] On Behalf Of Edwin A. Epstein III
Sent: Friday, September 28, 2018 3:21 PM
To: mrtg
Subject: Re: [mrtg] Graphing Uptime

CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe.

Hi Daniel,

Yes that example was horribly bodged. I haven't inspected the code, but I suspect MRTG works with the value returned by SNMP. For example, I receive this:

SNMPv2-MIB::sysUpTime.0 = Timeticks: (105630500) 12 days, 5:25:05.00

That cannot be graphed because it is not a number. Everything that MRTG graphs must be turned into some number. The example is also horribly bodged because it's trying to use a bandwidth graph instead of a gauge. MRTG provides for graphing values like CPU load, Memory, and Free disk space. You really want to grab the most recent book as it will tell you how to construct these. I'll give you an example:

Target[the_graph]:        1.3.6.1.4.1.32050.2.1.27.5.1&1.3.6.1.4.1.32050.2.1.27.5.1:snmp_community_name at 10.0.0.1:::::2 * -1.1034882
Options[the_graph]:       unknaszero,gauge,growright,nopercent,expscale,noo
SetEnv[the_graph]:        MRTG_INT_IP="No Ip" MRTG_INT_DESCR="n/a"
Colours[the_graph]:       ORANGE#dd8811,NONE#000000,VIOLET#0000ff,DARK GREEN#006600
Title[the_graph]:         Voltage Monitor
MaxBytes[the_graph]:      850
AbsMax[the_graph]:        850
XSize[the_graph]:         600

All of these directives are explained in the book. The two most important ones are the Target and Options directives. The gauge option is what makes it a gauge graph, and the noo option suppresses one side of the graph (input or output). With the directives you can construct your own custom graph with correct units for uptime, and a scale that will make sense. You can control titles, legend values, etc.

Your first issue is how to convert 'Timeticks: (105630500) 12 days, 5:25:05.00' to a number. I would suggest graphing the hours of uptime. Even after a few years of uptime, the value itself will be less than 100,000 and probably graph well over time.

MRTG provides for pre-processing of SNMP values before they are passed to MRTG. I'm performing math before I use the voltage value. Since I'm pretty sure that the math is any valid perl statement, you might be able to get away with Perl. That being said, you may be best served by simply creating your own data collection plug-in, which is thankfully easier done than said. Straight from the book:

Target[ezwf]: `/usr/local/bin/mrtg-scripts -a 1`

All you need to is create a bash script that pipes your snmpwalk output into a awk, and then convert the returned value into the number of hours. Timeticks can be converted to hours: Hours = Timeticks / 100 / 60 / 60.

Something like:

uptime=`snmpwalk -v1 -c public 10.0.0.1 SysUptime | awk -F'[()]' '{print $2}'`
let hours=uptime
let hours=$hours/100/60/60
echo $hours

If you run that bash and pass it into MRTG, with directives to create a gauge type graph, you should get a fairly nifty uptime graph. With correct units for time as a bonus.

Sincerely,

Edwin A Epstein, III
Rhinobee Internet Services
707.237.7504 ext 209
707.737.0288 Mobile

----- Original Message -----
From: "mrtg-request" <mrtg-request at lists.oetiker.ch>
To: "mrtg" <mrtg at lists.oetiker.ch>
Sent: Friday, September 28, 2018 3:00:02 AM
Subject: mrtg Digest, Vol 132, Issue 1

Send mrtg mailing list submissions to
        mrtg at lists.oetiker.ch

To subscribe or unsubscribe via the World Wide Web, visit
        https://lists.oetiker.ch/cgi-bin/listinfo/mrtg
or, via email, send a message with subject or body 'help' to
        mrtg-request at lists.oetiker.ch

You can reach the person managing the list at
        mrtg-owner at lists.oetiker.ch

When replying, please edit your Subject line so it is more specific
than "Re: Contents of mrtg digest..."

Today's Topics:

   1. Graphing uptime (Daniel Beardsmore)

----------------------------------------------------------------------

Message: 1
Date: Fri, 28 Sep 2018 10:06:23 +0100
From: "Daniel Beardsmore" <resident at telcontar.net>
To: <mrtg at lists.oetiker.ch>
Subject: [mrtg] Graphing uptime
Message-ID: <041801d4570a$88f67650$9ae362f0$@telcontar.net>
Content-Type: text/plain; charset="us-ascii"

Hello

I can see that graphing uptime is possible, as you can see here:

http://www.hotelsvillegia.com/mrtg/uptime.html

The HTML pages report uptime in the format: "163 days, 21:07:10"

If I check manually, I get this:

snmpget -v2c -c somecommunity somehost 1.3.6.1.2.1.1.3.0

DISMAN-EVENT-MIB::sysUpTimeInstance = Timeticks: (1415941565) 163 days,
21:10:15.65

The format is almost the same, but the latter contains the full centisecond
accuracy. You do nonetheless get the raw number included.

Now, using this in MRTG yields:

2018-09-27 19:56:04 -- 2018-09-27 19:51:33: WARNING: Expected a number but
got '163 days, 7:17:10'

Looking at the source code, I cannot determine quite how uptime is
processed. It seems odd that the format is almost the same (without the
centiseconds), which suggests (along with other code) that MRTG receives
pre-formatted output, and then has to scrape out the useful bits. (Which is
just plain horrible if this is true.)

Am I right in thinking that MRTG presently has no way to extract the raw
figure here? It seems that the SNMP library is formatting the data
prematurely and MRTG just works with that preformatted value as it suits its
own purposes, but that you cannot get the raw data out if you choose, for
example if you want to record uptime as a graph for checking for reboots.

In the example posted, I suspect that was bodged to get that to work.

Regards

Daniel.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.oetiker.ch/pipermail/mrtg/attachments/20180928/8eacb971/attachment-0001.html>

------------------------------

Subject: Digest Footer

_______________________________________________
mrtg mailing list
mrtg at lists.oetiker.ch
https://lists.oetiker.ch/cgi-bin/listinfo/mrtg

------------------------------

End of mrtg Digest, Vol 132, Issue 1
************************************
(null)

_______________________________________________
mrtg mailing list
mrtg at lists.oetiker.ch
https://lists.oetiker.ch/cgi-bin/listinfo/mrtg