What is this?

This knowledgebase contains questions and answers about PRTG Network Monitor and network monitoring in general.

Learn more

PRTG Network Monitor

Intuitive to Use. Easy to manage.
More than 500,000 users rely on Paessler PRTG every day. Find out how you can reduce cost, increase QoS and ease planning, as well.

Free Download

Top Tags


View all Tags

DHCP server monitoring

Votes:

2

It's possible to monitor DHCP service from "client side"?

DHCP service provided by CISCO equipment.

cisco dhcp howto prtg sensor

Created on Mar 11, 2010 3:04:47 PM

Last change on Mar 12, 2010 10:29:41 AM by  Daniel Zobel [Product Manager]



Best Answer

Accepted Answer

Votes:

0

What I have done is use the remote probe software on inexpensive netbooks. We have placed them in the field with static IP addresses assigned by our DHCP server. We have assigned really short lease times to these Static entries. This way you get a probe on the network you want to query you DHCP server on. This really works well in our environment as we have lots of subnets and we relay DHCP through our layer 3 routers. If the probe goes down and the network gear still appears to be up we start looking. This does not solve the problem of trying to determine if you have a rogue DHCP server on your network as a static address would be a more detailed response then your average wireless access point or home router might send out. DHCP clients tend to prefer the response from the DHCP server that provided the most detailed information first.

I'd add this setup with netbooks also allows us to do some QOS mesh testing when needed too.

- Andrew

Created on Apr 17, 2010 2:17:27 AM



7 Replies

Votes:

1

I think so. You need to load the CISCO MIB into PRTG and scan the device using that selected mib.

You'll need to use the MIB Importer tool found on the PRTG website.

Created on Mar 11, 2010 9:38:52 PM

Last change on Mar 12, 2010 9:47:52 AM by  Daniel Zobel [Product Manager]



Votes:

1

As I say before monitoring should be from client side because management console (and SNMP, I think) show a good status of DHCP service at device while problem occured.

Created on Mar 12, 2010 7:02:32 AM



Votes:

1

I'm not sure what you mean by client side. Do you want to monitor when the pool gets full? Or do you want to check that a request for an IP from the DHCP server was successful?

Created on Mar 12, 2010 1:35:27 PM



Votes:

1

Yes, I need to check that DHCP server is "talking" with clients (DHCP offer, acknowledgement).

Created on Mar 12, 2010 2:03:06 PM



Votes:

2

Yeah, SNMP isn't going to help you with that.

I know of this program: http://ks-soft.net/cgi-bin/phpBB/viewtopic.php?t=4231

It's a simple program the looks for a DHCP response. You would then need to program something to look for the response the program provides. Check the PRTG manual for setting up a custom exe sensor.

I don't know the best way, but you might have to write a vbs script, or batch file, that runs the command and based on the result returns a value that prtg can understand.

Created on Mar 12, 2010 3:51:13 PM

Last change on May 21, 2014 3:55:32 PM by  Gerald Schoch [Paessler Support]



Accepted Answer

Votes:

0

What I have done is use the remote probe software on inexpensive netbooks. We have placed them in the field with static IP addresses assigned by our DHCP server. We have assigned really short lease times to these Static entries. This way you get a probe on the network you want to query you DHCP server on. This really works well in our environment as we have lots of subnets and we relay DHCP through our layer 3 routers. If the probe goes down and the network gear still appears to be up we start looking. This does not solve the problem of trying to determine if you have a rogue DHCP server on your network as a static address would be a more detailed response then your average wireless access point or home router might send out. DHCP clients tend to prefer the response from the DHCP server that provided the most detailed information first.

I'd add this setup with netbooks also allows us to do some QOS mesh testing when needed too.

- Andrew

Created on Apr 17, 2010 2:17:27 AM



Votes:

0

See also: DHCP Sensor

Created on May 21, 2014 3:11:00 PM by  Gerald Schoch [Paessler Support]

Last change on May 21, 2014 3:54:50 PM by  Gerald Schoch [Paessler Support]




Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.