Devmon / MRTG
list Mv652
Hi, Could I get a quick-and-dirty explanation regarding the Devmon implementation in Xymon 4.3.x? The way I understand it, Devmon provides SNMP capabilities to Xymon so the monitoring server can poll SNMP capable devices. How is this different to Integrating MRTF data into XYMON, for example? If I am interesting in getting bandwidth for various device interfaces, I am assuming it is best to do via Devmon rather than integrate MRTG? Lastly, is there a readme / howto that explains devmon-xymon setup? Thanks, Mario
list Greg Hubbard
The devmon system is separate from Xymon -- they work as partners. Devmon can read the Xymon bb-hosts file to find directives, and it uses this information to configure itself for polling. Devmon discovers SNMP devices and monitors them according to its own set of templates. Devmon reports status to Xymon. The most recent versions of Xymon and Devmon supposedly allow data from Devmon to be graphed in Xymon displays so the two systems appear to be very integrated -- but I have not tried this myself. Devmon does the monitoring, and it uses its own device templates to control what gets monitored for each device type. The standard template library includes a number of device types, but not all devices are equal, and it takes a while to get the hang of the devmon template approach so you can make your own templates. The main devmon developer often participates on this list, but there are some devmon lists. GLH
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On 8/14/09, user-2e62ad6fd761@xymon.invalid <user-2e62ad6fd761@xymon.invalid> wrote:Hi, Could I get a quick-and-dirty explanation regarding the Devmon implementation in Xymon 4.3.x? The way I understand it, Devmon provides SNMP capabilities to Xymon so the monitoring server can poll SNMP capable devices. How is this different to Integrating MRTF data into XYMON, for example? If I am interesting in getting bandwidth for various device interfaces, I am assuming it is best to do via Devmon rather than integrate MRTG? Lastly, is there a readme / howto that explains devmon-xymon setup? Thanks, Mario
list Mv652
Thanks for that explanation. I'll take a look at the Devmon lists too. One of my concerns is 'over-monitoring' and consequently causing too much stress on the network and systems being monitored (including the monitoring server itself). A 5-minute average interface check would be too long for my needs. Should I be concerned if I set the snmp monitoring to a 1-minute average? We don't have many devices at the moment, but the network has potential to grow quite rapidly. I suppose this could be a general question of 'how much monitoring is too much much'? Some would say you could never have too much, but are there any benchmarks I can use to minimize any performance hits on my network caused by this monitoring? Mario
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Greg Hubbard writes: The devmon system is separate from Xymon -- they work as partners. Devmon can read the Xymon bb-hosts file to find directives, and it uses this information to configure itself for polling. Devmon discovers SNMP devices and monitors them according to its own set of templates. Devmon reports status to Xymon. The most recent versions of Xymon and Devmon supposedly allow data from Devmon to be graphed in Xymon displays so the two systems appear to be very integrated -- but I have not tried this myself. Devmon does the monitoring, and it uses its own device templates to control what gets monitored for each device type. The standard template library includes a number of device types, but not all devices are equal, and it takes a while to get the hang of the devmon template approach so you can make your own templates. The main devmon developer often participates on this list, but there are some devmon lists. GLH On 8/14/09, user-2e62ad6fd761@xymon.invalid <user-2e62ad6fd761@xymon.invalid> wrote:Hi, Could I get a quick-and-dirty explanation regarding the Devmon implementation in Xymon 4.3.x? The way I understand it, Devmon provides SNMP capabilities to Xymon so the monitoring server can poll SNMP capable devices. How is this different to Integrating MRTF data into XYMON, for example? If I am interesting in getting bandwidth for various device interfaces, I am assuming it is best to do via Devmon rather than integrate MRTG? Lastly, is there a readme / howto that explains devmon-xymon setup? Thanks, Mario
list Buchan Milne
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On Friday, 14 August 2009 15:08:33 user-2e62ad6fd761@xymon.invalid wrote:
Hi, Could I get a quick-and-dirty explanation regarding the Devmon implementation in Xymon 4.3.x?
Nothing has changed regarding Devmon in Xymon 4.3.x. However, Xymon itself has some basic native SNMP support, which is new in 4.3.x.
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The way I understand it, Devmon provides SNMP capabilities to Xymon so the monitoring server can poll SNMP capable devices. How is this different to Integrating MRTF data into XYMON, for example?
Devmon only polls devices, does conversion and formatting of data, which it then sends to Xymon as a normal status message. A devmon RRD collector is now shipped with Xymon (as of 4.2.2), that allows RRD graphs to be created by Xymon for any test/template that includes data intended for this purpose (using the rrd option to the TABLE operator in the template file on the devmon side), if the test is mapped to use this collector (in the TEST2RRD variable in hobbitserver.cfg). Besides the graphs, devmon will also change the "colour" of the tests based on thresholds, allowing you to alert on SNMP data (including non-graph data).
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If I am interesting in getting bandwidth for various device interfaces, I am assuming it is best to do via Devmon rather than integrate MRTG?
I think it is probably easier to get bandwidth graphs up with Devmon than with MRTG, and alerts based on link utilisation will be available out-the-box.
Lastly, is there a readme / howto that explains devmon-xymon setup?
If you're on a distro that provides devmon, it is more or less a matter of: # $install devmon (where install=urpmi for Mandriva, or $install="yum install" on RHEL or CentOS if you have added the repo at e.g. http://staff.telkomsa.net/packages/rhel5/xymon) # vi /etc/devmon.cfg (set your SNMP community strings in the SNMPCIDS variable, the others should have adequate defaults) # /etc/init.d/devmon readbbhosts # /etc/init.d/devmon start If you're adventurous, you could add the weathermap (see http://staff.telkomsa.net/~bgmilne/xymon/). If you're not on a distro with packages available, please see the INSTALLATION and USING files shipped in the docs directory. Regards, Buchan
list Mv652
That's helped to explain things very nicely, thank you. I am, in fact using CENTOS, so should have it setup quite soon. I'll place any futrure devmon questions in the relevant lists. Regards, Mario
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Buchan Milne writes: On Friday, 14 August 2009 15:08:33 user-2e62ad6fd761@xymon.invalid wrote:Hi, Could I get a quick-and-dirty explanation regarding the Devmon implementation in Xymon 4.3.x?Nothing has changed regarding Devmon in Xymon 4.3.x. However, Xymon itself has some basic native SNMP support, which is new in 4.3.x.The way I understand it, Devmon provides SNMP capabilities to Xymon so the monitoring server can poll SNMP capable devices. How is this different to Integrating MRTF data into XYMON, for example?Devmon only polls devices, does conversion and formatting of data, which it then sends to Xymon as a normal status message. A devmon RRD collector is now shipped with Xymon (as of 4.2.2), that allows RRD graphs to be created by Xymon for any test/template that includes data intended for this purpose (using the rrd option to the TABLE operator in the template file on the devmon side), if the test is mapped to use this collector (in the TEST2RRD variable in hobbitserver.cfg). Besides the graphs, devmon will also change the "colour" of the tests based on thresholds, allowing you to alert on SNMP data (including non-graph data).If I am interesting in getting bandwidth for various device interfaces, I am assuming it is best to do via Devmon rather than integrate MRTG?I think it is probably easier to get bandwidth graphs up with Devmon than with MRTG, and alerts based on link utilisation will be available out-the-box.Lastly, is there a readme / howto that explains devmon-xymon setup?If you're on a distro that provides devmon, it is more or less a matter of: # $install devmon (where install=urpmi for Mandriva, or $install="yum install" on RHEL or CentOS if you have added the repo at e.g. http://staff.telkomsa.net/packages/rhel5/xymon) # vi /etc/devmon.cfg (set your SNMP community strings in the SNMPCIDS variable, the others should have adequate defaults) # /etc/init.d/devmon readbbhosts # /etc/init.d/devmon start If you're adventurous, you could add the weathermap (see http://staff.telkomsa.net/~bgmilne/xymon/). If you're not on a distro with packages available, please see the INSTALLATION and USING files shipped in the docs directory. Regards, Buchan
list Thomas Leavitt
I've just got devmon set up and working... more or less. I've hacked the Redhat init.d script, but I'd rather have a Debian/Ubuntu native start up script if someone's already written one. I've no experience with SNMP, but I think I basically get the idea of how to develop templates after looking at the wikibook section on devmon, so I guess I'll be developing a template for the Netgear STM300 unless someone's already done it. :) Netgear ReadyNAS 1100? :) Regards, Thomas Leavitt
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On Mon, Aug 17, 2009 at 7:49 AM, Buchan Milne<user-9b139aff4dec@xymon.invalid> wrote:On Friday, 14 August 2009 15:08:33 user-2e62ad6fd761@xymon.invalid wrote:Hi, Could I get a quick-and-dirty explanation regarding the Devmon implementation in Xymon 4.3.x?Nothing has changed regarding Devmon in Xymon 4.3.x. However, Xymon itself has some basic native SNMP support, which is new in 4.3.x.The way I understand it, Devmon provides SNMP capabilities to Xymon so the monitoring server can poll SNMP capable devices. How is this different to Integrating MRTF data into XYMON, for example?Devmon only polls devices, does conversion and formatting of data, which it then sends to Xymon as a normal status message. A devmon RRD collector is now shipped with Xymon (as of 4.2.2), that allows RRD graphs to be created by Xymon for any test/template that includes data intended for this purpose (using the rrd option to the TABLE operator in the template file on the devmon side), if the test is mapped to use this collector (in the TEST2RRD variable in hobbitserver.cfg). Besides the graphs, devmon will also change the "colour" of the tests based on thresholds, allowing you to alert on SNMP data (including non-graph data).If I am interesting in getting bandwidth for various device interfaces, I am assuming it is best to do via Devmon rather than integrate MRTG?I think it is probably easier to get bandwidth graphs up with Devmon than with MRTG, and alerts based on link utilisation will be available out-the-box.Lastly, is there a readme / howto that explains devmon-xymon setup?If you're on a distro that provides devmon, it is more or less a matter of: # $install devmon (where install=urpmi for Mandriva, or $install="yum install" on RHEL or CentOS if you have added the repo at e.g. http://staff.telkomsa.net/packages/rhel5/xymon) # vi /etc/devmon.cfg (set your SNMP community strings in the SNMPCIDS variable, the others should have adequate defaults) # /etc/init.d/devmon readbbhosts # /etc/init.d/devmon start If you're adventurous, you could add the weathermap (see http://staff.telkomsa.net/~bgmilne/xymon/). If you're not on a distro with packages available, please see the INSTALLATION and USING files shipped in the docs directory. Regards, Buchan
list Thomas Leavitt
a) I've implemented devmon, my very small and resource strapped client is very happy... I'm still in the process of working the bugs out. devmon appears to go purple (and all reports dependent on it) periodically, and then not come back... did that last time I was here, wasn't sure what caused it. Just did it a few minutes ago. Wasn't sure what caused it, and was too distracted and tired to carefully trace out what I did to fix it again (stopped, started devmon, xymon, and manually ran devmon) after it was working for most of three hours. I really need an Ubuntu specific init.d script. Ubuntu's use of upstart in hardy means that the "status" command, for instance, is dependent on stuff in /etc/event.d to work, and I really don't want to have to manually re-create all that... surely someone else is running devmon on a Debian derivative, and has a functional initialization script? b) I've begun to implement weathermap. I'm trying to figure out a rational process for creating a map of our small network... the weathermap.conf example appears to have been generated using php-weathermap... do I really need to implement that, so I get the editor for it? Thomas
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On Mon, Aug 17, 2009 at 7:49 AM, Buchan Milne <user-9b139aff4dec@xymon.invalid>wrote:
On Friday, 14 August 2009 15:08:33 user-2e62ad6fd761@xymon.invalid wrote:Hi, Could I get a quick-and-dirty explanation regarding the Devmon implementation in Xymon 4.3.x?Nothing has changed regarding Devmon in Xymon 4.3.x. However, Xymon itself has some basic native SNMP support, which is new in 4.3.x.The way I understand it, Devmon provides SNMP capabilities to Xymon so the monitoring server can poll SNMP capable devices. How is this different to Integrating MRTF data into XYMON, for example?Devmon only polls devices, does conversion and formatting of data, which it then sends to Xymon as a normal status message. A devmon RRD collector is now shipped with Xymon (as of 4.2.2), that allows RRD graphs to be created by Xymon for any test/template that includes data intended for this purpose (using the rrd option to the TABLE operator in the template file on the devmon side), if the test is mapped to use this collector (in the TEST2RRD variable in hobbitserver.cfg). Besides the graphs, devmon will also change the "colour" of the tests based on thresholds, allowing you to alert on SNMP data (including non-graph data).If I am interesting in getting bandwidth for various device interfaces, I am assuming it is best to do via Devmon rather than integrate MRTG?I think it is probably easier to get bandwidth graphs up with Devmon than with MRTG, and alerts based on link utilisation will be available out-the-box.Lastly, is there a readme / howto that explains devmon-xymon setup?If you're on a distro that provides devmon, it is more or less a matter of: # $install devmon (where install=urpmi for Mandriva, or $install="yum install" on RHEL or CentOS if you have added the repo at e.g. http://staff.telkomsa.net/packages/rhel5/xymon) # vi /etc/devmon.cfg (set your SNMP community strings in the SNMPCIDS variable, the others should have adequate defaults) # /etc/init.d/devmon readbbhosts # /etc/init.d/devmon start If you're adventurous, you could add the weathermap (see http://staff.telkomsa.net/~bgmilne/xymon/). If you're not on a distro with packages available, please see the INSTALLATION and USING files shipped in the docs directory. Regards, Buchan