24.09.2019by admin

Centreo Monitoring Dhcp Scopes

Monitoring and Troubleshooting the DHCP ServerTechieBird Quick LinksOther LinksMonitoring and Troubleshooting the DHCP ServerYou can use the Event Viewer tool, located in the Administrative Tools folder, to monitor DHCP activity. Event Viewer stores events that are logged in the system log, application log, and security log.

Multiple Dhcp Scopes
Centreo Monitoring Dhcp Scopes 1

The system log contains events that are associated with the operating system. The application log stores events that pertain to applications running on the computer. Events that are associated with auditing activities are logged in the security log. All events that are DHCP-specific are logged in the System log. The DHCP system event log contains events that are associated with activities of the DHCP service and DHCP server, such as when the DHCP server started and stopped, when DHCP leases are close to being depleted, and when the DHCP database is corrupt.A few DHCP system event log IDs are listed below:.Event ID 1037 (Information): Indicates that the DHCP server has begun to clean up the DHCP database.Event ID 1038 (Information): Indicates that the DHCP server cleaned up the DHCP database for unicast addresses:.0 IP address leases were recovered.0 records were deleted. Event ID 1046 (Error): Indicates that the DHCP service running on the server has determined that it is not authorized to start to service DHCP clients.Using System Monitor to Monitor DHCP ActivityThe System Monitor utility is the main tool for monitoring system performance. System Monitor can track various processes on the Windows system in real time.

Monitor and Manage Windows DHCP Server Scopes When managing your IP Address space, it is often required to relate your available and used IP Addresses to your DHCP Servers. IP Addresses in most organizations today are served via DHCP Servers as it is much easier to allocate different scopes for different needs. Monitoring DHCP leases. Setting this up is pretty simple if you already have PRTG installed. Here are the steps to monitor the DHCP scopes on a Windows 2012 R2 server: Make sure your Windows server has the SNMP service enabled along with the proper SNMP community string necessary.

The utility uses a graphical display that you can use to view current data, or log data. You can specify specific elements or components that should be tracked on the local computer and remote computers. You can determine resource usage by monitoring trends. System Monitor can be displayed in a graph, histogram, or report format. System Monitor uses objects, counters and instances to monitor the systemSystem Monitor is a valuable tool when you need to monitor and troubleshooting DHCP traffic being passed between the DHCP server and DHCP clients.

The IP address type should be displayed as being Assigned By DHCP.If after the above checks, you can conclude that the IP address was assigned to the client by the DHCP server, some other network issue is the cause of the DHCP server connectivity issues being experienced. The issue is not due to an IP addressing issue on the client.When clients have the incorrect IP address, it was probably due o the computer not being able to contact the DHCP server. When this occurs, the computer assigns its own IP address through Automatic Private IP Addressing (APIPA).Computers could be unable to contact the DHCP server for a number of reasons:.A problem might exist with the hardware or software of the DHCP server.A data-link protocol issue could be preventing the computer from communicating with the network.The DHCP server and the client are on different LANs and there is no DHCP Relay Agent. When troubleshooting the scope configured for the DHCP server:. heck that the scope is enabled. heck whether all the available IP leases have already been assigned to clientsA few troubleshooting strategies which you can use when a DHCP client obtains an IP address from the incorrect scope are summarized below:.First determine whether competing DHCP servers exist on your network.

Use the Dhcploc.exe utility, included with the Windows Support Tools to locate rogue DHCP servers that are allocating IP addresses to clients.If no rogue DHCP servers are located through the Dhcploc.exe utility, your next step is to verify that each DHCP server is allocating IP address leases from unique scopes. If you have DHCP servers that contain multiple scopes, check that each of these scopes is configured correctly.Troubleshooting DHCP Database IssuesThe DHCP service uses a number of database files to maintain DHCP-specific data or information on IP addresses leases, scopes, superscopes, and DHCP options. The DHCP database files that are located in the systemrootSystem32DHCP folder are listed below.

These files remain open while the DHCP service is running on the server.

Here is a way to monitor DHCP statistics per scope: SummaryMonitor DHCP statistics, using DHCP MIB and PRTG SNMP-Custom sensors. Install the snmp service in your DHCP server if not installed, using add/remove windows components. Then go to Network and management tools and install the service.2. Once the snmp service is installed, click on it, then click on the security tab. Specify the community name and hosts allowed to get snmp info.3. Check the available OID's in the You will find all the relevant MIB values related to the DHCP scope statistics: dhcpScope1.3.6.1.4.1.311.1.3.2scopeTable1.3.6.1.4.1.311.1.3.2.1scopeTableEntry1.3.6.1.4.1.311.1.3.2.1.1subnetAdd1.3.6.1.4.1.311.1.3.2.1.1.1.

ScopeAddressnoAddInUse (Used IPs)1.3.6.1.4.1.311.1.3.2.1.1.2. ScopeAddressnoAddFree ((Available IPs))1.3.6.1.4.1.311.1.3.2.1.1.3.

Add a PRTG or Sensor with the MIB value required, and make sure you modify the SNMP credentials. Example, if your scope is 192.168.100.0 and you want to know the number of used IP's, the complete OID will look like this: 1.3.6.1.4.1.311.1.3.2.1.1.2. Then You can add notifications and thresholds per sensor. Ex.: Set a notification to send an email/sms if the number of available IPs are below 10.Edited by Mod, thanks for the contribution. Some notes/comments:. Since the data is a SNMP Table, this is a great opportunity to try-out the.

If you encounter Generic Error (SNMP error # 5) on Windows Server 2012, please refer to. If you wish to monitor DHCP using powershell instead, there are several customer-shared scripts available, pick the one that suits you best:.Best Regards,Luciano Lingnau Paessler Support.

Once the snmp service is installed, click on it, then click on the security tab. Specify the community name and hosts allowed to get snmp info.3. Check the available OID's in the You will find all the relevant MIB values related to the DHCP scope statistics: dhcpScope1.3.6.1.4.1.311.1.3.2scopeTable1.3.6.1.4.1.311.1.3.2.1scopeTableEntry1.3.6.1.4.1.311.1.3.2.1.1subnetAdd1.3.6.1.4.1.311.1.3.2.1.1.1.

Multiple Dhcp Scopes

ScopeAddressnoAddInUse (Used IPs)1.3.6.1.4.1.311.1.3.2.1.1.2. ScopeAddressnoAddFree ((Available IPs))1.3.6.1.4.1.311.1.3.2.1.1.3. Add a PRTG or Sensor with the MIB value required, and make sure you modify the SNMP credentials. Example, if your scope is 192.168.100.0 and you want to know the number of used IP's, the complete OID will look like this: 1.3.6.1.4.1.311.1.3.2.1.1.2. Then You can add notifications and thresholds per sensor.

Centreo Monitoring Dhcp Scopes 1

Ex.: Set a notification to send an email/sms if the number of available IPs are below 10.Edited by Mod, thanks for the contribution. Some notes/comments:. Since the data is a SNMP Table, this is a great opportunity to try-out the.

When using a windows DHCP server and you have multiple scopes the above OIDs need to have the subnet's IP address of the scope at the end of the OID. In other words if you want to see the free IP's and you have 2 scopes for subnets 10.10.0.0 and 10.20.0.0 you would use the OIDs 1.3.6.1.4.1.311.1.3.2.1.1.3.10.10.0.0 and 1.3.6.1.4.1.311.1.3.2.1.1.3.10.20.0.0all the other OIDs listed above work the same way when you have multiple scopes.Hope this helps someone! We are using the above method to successfully monitor many of our DHCP scopes. (Thank you for your excellent posts.)The problem that we are now having is that we are using a (Microsoft) super scope with two class C ranges for wireless clients.

Using the above method requires two separate sensors which alert us when either range is exhausted of free addresses. The problem with that is that what we ACTUALLY need to be notified of is when BOTH scopes are exhausted.- Is there a way to modify the OIDs listed above to monitor a super-scope?- Or is there a way to create a custom sensor that uses Regular Expressions to compare two or more existing sensors?- Or is there another solution all together that we haven't considered?Thanks in advance for any assistance.:). So I was facing the same problem here, trying to monitor DHCP scopes using PRTG, the DHCP server being a role on a Windows Server 2012 R2. I found the following:.

when running SNMP as a service, I get the ' error #5' message. when stopping the SNMP service, instead running C:WindowsSystem32snmp.exe as SYSTEM from a scheduled task that runs at server startup, it runs perfectly each time. The C:Windowssystem32snmp.exe application has to be allowed through Windows Firewall as simply allowing the SNMP service does not work.

Is someone else seeing this?. Is this a usable fix or does this tear a giant security hole into that server by running the service as SYSTEM? Hello randhall,thank you for your reply.Please note that we can only offer limited support for customer-shared scripts.

However:. Make sure that you meet the requirements to run powershell sensors as described. Since there's a $env:computername, the script most likely requires you to enable the Environment: Set placeholders as environment values option in the sensor's settings.

The sensor needs to run with an account that has sufficient privileges to query information from the remote (monitored system) via powershell remoting. The remote system must allow remote powershell connections.As a workaround I suggest that you try the.Best Regards,Luciano Lingnau Paessler Support.

I have been using DHCP 2012 R2 with PRTG for monitoring specific pool and with C:Windowssystem32snmp.exe running at start up works for a while, and after that sensor goes into error/down state. After rebooting DHCP server all is ok until some time (around week) and again all sensors used to monitor IP pools are down. Since this solution is not reliable I cannot use it in enterprise.I was happy and loved that was able to monitor pools using PRTG, but now I guess I have to find another solution.The option with the script is working for anybody? Maybe I should try that and forget about the sensor that dying after a week.

Hello SwissJay and rhilauthank you for your replies.@ rhilau - Many thanks for the script, it's a thing of beauty.Very tidy and extra points for using a custom lookup.:)Regarding @ SwissJay's changes/notes: made a few edits so the script would run on our PRTG server as we did not add the DHCP mgmt modules to it, so it runs the Powershell commands on the DHCP server remotely,I also prefer this approach. Having to install as little software as possible on the remote probe. Running it via Invoke-Command definitively adds the Skookum to it. Had to round the percentages returned by the script as PRTG would show 0% otherwise in the GUI (could be related to localization perhaps?!)I'm able to confirm an open bug with the API for Custom sensors (XML based), when PRTG is unable to identify a numerical value between the it displays the value of 0 (zero) instead of producing a parse error. Enabling the 'Log Result to Disk' would tell you what the actual output was. But it could definitively be a localization issue like dot vs comma.Best Regards,Luciano Lingnau Paessler Support.