You can use a topology-only discovery to map your network. This kind of discovery does not discover potential clients. The topology-only Network Discovery relies on SNMP.

When mapping your network topology, you must configure the Maximum hops on the SNMP tab in the Network Discovery Properties dialog box. Just a few hops can help control the network bandwidth that is used when discovery runs. As you discover more of your network, you can increase the number of hops to gain a better understanding of your network topology.

After you understand your network topology, you can configure additional properties for Network Discovery to discover potential clients and their operating systems while you are using available configurations to limit the network segments that Network Discovery can search.

You can configure Network Discovery to search specific subnets during a discovery run. By default, Network Discovery searches the subnet of the server that runs discovery. Any additional subnets that you configure and enable apply only to Simple Network Management Protocol (SNMP) and Dynamic Host Configuration Protocol (DHCP) search options. When Network Discovery searches domains, it is not limited by configurations for subnets.

If you specify one or more subnets on the Subnets tab in the Network Discovery Properties dialog box, only the subnets that are marked as Enabled are searched.

When you disable a subnet, it is excluded from discovery, and the following conditions apply:

• SNMP-based queries do not run on the subnet
  
  
• DHCP servers do not reply with a list of resources located on the subnet
  
  
• Domain-based queries can discover resources that are located on the subnet
  
  

You can configure Network Discovery to search a specific domain or set of domains during a discovery run. By default, Network Discovery searches the local domain of the server that runs discovery.

If you specify one or more domains on the Domains tab in the Network Discovery Properties dialog box, only the domains that are marked as Enabled are searched.

When you disable a domain, it is excluded from discovery, and the following conditions apply:

• Network Discovery does not query domain controllers in that domain
  
  
• SNMP-based queries can still run on subnets in the domain
  
  
• DHCP servers can still reply with a list of resources located in the domain
  
  

You configure Network Discovery to search a specific SNMP community or set of communities during a discovery run. By default, the community name of public is configured for use.

Network Discovery uses community names to gain access to routers that are SNMP devices. A router can supply Network Discovery with information about other routers and subnets that are linked to the first router.

Note

SNMP community names resemble passwords. Network Discovery can get information only from an SNMP device for which you have specified a community name. Each SNMP device can have its own community name, but often the same community name is shared among several devices. Additionally, most SNMP devices have a default community name of public. However, some organizations delete the public community name from their devices as a security precaution.

If multiple SNMP communities are displayed on the SNMP tab in the Network Discovery Properties dialog box, Network Discovery searches them in the order in which they are displayed. To help minimize network traffic that is generated by attempts to contact a device by using different names, ensure that the most frequently used names are at the top of the list.

Note
In addition to using the SNMP Community name, you can specify the IP address or resolvable name of a specific SNMP device. You configure the IP address or resolvable name for a specific device on SNMP Devices tab in the Network Discovery Properties dialog box.

You can configure Network Discovery to use a specific DHCP server or multiple servers to discover DHCP clients during a discovery run.

Network Discovery searches each DHCP server that you specify on the DHCP tab in the Network Discovery Properties dialog box. If the server that is running discovery leases its IP address from a DHCP server, you can configure discovery to search that DHCP server by selecting the Include the DHCP server that the site server is configured to use check box.

Note
To successfully configure a DHCP server in Network Discovery, your environment must support IPv4. You cannot configure Network Discovery to use a DHCP server in a native IPv6 environment.

1. In the Configuration Manager console, click Administration.

2. In the Administration workspace, expand Hierarchy Configuration, and then click Discovery Methods.

3. Select Network Discovery for the site where you want to run Network Discovery.

4. On the Home tab, in the Properties group, click Properties.

   • On the General tab, select the Enable network discovery check box, and then select Topology from the Type of discovery options.
     
     
   • On the Subnets tab, select the Search local subnets check box.
     
     

     Tip
     If you know the specific subnets that constitute your network, you can clear the Search local subnets check box and use the New icon to add the specific subnets that you want to search. For large networks, it is often best to search only one or two subnets at a time to minimize the use of network bandwidth.

   • On the Domains tab, select the Search local domain check box.
     
     
   • On the SNMP tab, use the Maximum hops drop-down list to specify how many router hops Network Discovery can take in mapping your topology.
     
     

     Tip
     When you first map your network topology, configure just a few router hops to minimize the use of network bandwidth.

5. On the Schedule tab, click the New icon to set a schedule for running Network Discovery.

   Note
   You cannot assign a different discovery configuration to separate Network Discovery schedules. Each time Network Discovery runs, it uses the current discovery configuration.

6. Click OK to accept the configurations. Network Discovery runs at the scheduled time.

1. In the Configuration Manager console, click Administration.

2. In the Administration workspace, expand Hierarchy Configuration, and then click Discovery Methods.

3. Select Network Discovery for the site where you want to run Network Discovery.

4. On the Home tab, in the Properties group, click Properties.

5. On the General tab, select the Enable network discovery check box, and then select the type of discovery that you want to run from the Type of discovery options.

6. To configure discovery to search subnets, click the Subnets tab, and on the Subnets tab, configure one or more of the following options:

   • To run discovery on subnets that are local to the computer that runs discovery, select the Search local subnets check box.
     
     
   • To search a specific subnet, the subnet must be listed in Subnets to search, and have a Search value of Enabled:
     
     
     1. If the subnet is not listed, click the New icon . In the New Subnet Assignment dialog box, enter the Subnet and Mask information, and then click OK. By default, a new subnet is enabled for search.
        
        
     2. To change the Search value for a listed subnet, select the subnet, and then click the Toggle icon to toggle the value between Disabled and Enabled.
        
        

7. To configure discovery to search domains, click the Domains tab, and on the Domains tab, configure one or more of the following options:

   • To run discovery on the domain of the computer that runs discovery, select the Search local domain check box.
     
     
   • To search a specific domain, the domain must be listed in Domains and have a Search value of Enabled:
     
     
     1. If the domain is not listed, click the New icon , and in the Domain Properties dialog box, enter the Domain information, and then click OK. By default, a new domain is enabled for search.
        
        
     2. To change the Search value for a listed domain, select the domain, and then click the Toggle icon to toggle the value between Disabled and Enabled.
        
        

8. To configure discovery to search specific SNMP community names for SNMP devices, click the SNMP tab, and on the SNMP tab, configure one or more of the following options:

   • To add an SNMP community name to the list of SNMP Community names, click the New icon , and in the New SNMP Community Name dialog box, specify the Name of the SNMP community, and then click OK.
     
     
   • To remove an SNMP community name, select the community name, and then click the Delete icon .
     
     
   • To adjust the search order of SNMP community names, select a community name, and then click the Move Item Up icon , or the Move Item Down icon . When discovery runs, community names are searched in a top-to-bottom order.
     
     

     Note
     Network Discovery uses SNMP community names to gain access to routers that are SNMP devices. A router can inform Network Discovery about other routers and subnets linked to the first router.

     • SNMP community names resemble passwords.
       
       
     • Network Discovery can get information only from an SNMP device for which you have specified a community name.
       
       
     • Each SNMP device can have its own community name, but often the same community name is shared among several devices
       
       
     • Most SNMP devices have a default community name of Public which can be used if you do not know any other community names. However, some organizations delete the Public community name from their devices as a security precaution.
       
       

9. To configure the maximum number of router hops for use by SNMP searches, click the SNMP tab, and on the SNMP tab, select the number of hops from the Maximum hops drop-down list.

10. To configure SNMP Devices, click the SNMP Devices tab, and on the SNMP tab, if the device is not listed, click the New icon . In the New SNMP Device dialog box, specify the IP address or device name of the SNMP device, and then click OK.

    Note
    If you specify a device name, Configuration Manager must be able to resolve the NetBIOS name to an IP address.

11. To configure discovery to query specific DHCP servers for DHCP clients, click the DHCP tab, and on the DHCP tab, configure one or more of the following options:

    • To query the DHCP server on the computer that is running discovery, select the Always use the site server’s DHCP server check box.
      
      

      Note
      To use this option, the server must lease its IP address from a DHCP server and cannot use a static IP address.

    • To query a specific DHCP server, click the New icon , and in the New DHCP Server dialog box, specify the IP address or server name of the DHCP server, and then click OK.
      
      

      Note
      If you specify a server name, Configuration Manager must be able to resolve the NetBIOS name to an IP address.

12. To configure when discovery runs, click the Schedule tab, and on the Schedule tab, click the New icon to set a schedule for running Network Discovery.

    You can configure multiple schedules for Network Discovery that include multiple recurring schedules and multiple schedules that have no recurrence.

    Note
    If multiple schedules are displayed on the Schedule tab at the same time, all schedules result in a run of Network Discovery as it is configured at the time indicated in the schedule. This is also true for recurring schedules.

13. Click OK to save your configurations.

1. In the Configuration Manager console, click Monitoring.

2. In the Monitoring workspace, expand System Status, and then click Status Message Queries.

3. Select All Status Messages.

4. On the Home tab, in the Status Message Queries group, click Show Messages.

5. Select the Select date and time drop-down list and select a value that includes how long ago the discovery started, and then click OK to open the Configuration Manager Status Message Viewer.

   Tip
   You can also use the Specify date and time option to select a given date and time that you ran discovery. This option is useful when you ran Network Discovery on a given date and want to retrieve messages from only that date.

6. To validate that Network Discovery has finished, search for a status message that has the following details:

   • Message ID: 502
     
     
   • Component: SMS_NETWORK_DISCOVERY
     
     
   • Description: This component stopped
     
     

   If this status message is not present, Network Discovery has not finished.

7. To validate when Network Discovery started, search for a status message that has the following details:

   • Message ID: 500
     
     
   • Component: SMS_NETWORK_DISCOVERY
     
     
   • Description: This component started
     
     

   This information verifies that Network Discovery started. If this information is not present, reschedule Network Discovery.