After you configure a discovery, you can start and, if necessary, stop the discovery.
Make any required discovery configuration changes before you launch the discovery.
You can start the following types of discovery:
Discovery
Run a full discovery to discover your network for the first time, or to refresh the network topology if you know the network has changed.
Partial discovery
Run a partial discovery if you know that the changes to your network are limited to a small number of devices. You need to configure scoping and seeding as part of starting each partial discovery. If the relationship of the devices that are in scope with their neighboring devices has changed, then the neighboring devices may also be discovered. If the partial discovery needs to discover a large amount of devices based on connectivity information, then a full discovery is started.
Note: If you stop a running discovery, you must then do a full discovery before you are able to do a partial discovery.
To start a discovery, complete the following steps.
1. Click Discovery > Network Discovery Status.
2. Select the domain in which you want to run a discovery from the Domain menu. You can start to type the name of the domain, and matching domains are listed below the Domain field.
3. Start a full or partial discovery:
v To start a full discovery, click Start Discovery only. The discovery starts.
Important: In Network Manager V3.9 there is no longer any need to press Stop Discoveryand then Start Discovery in order to pick up discovery configuration changes. Network Manager picks up any saved discovery
configuration changes when you click Start Discovery .
v To start a partial discovery, click the downward-facing arrow next to the Start Discovery button and select Start Partial Discovery from the menu (if a full discovery has not been run since the last time that the discovery engine, ncp_disco, was started, the option to start a partial
discovery is grayed out). The Partial Discovery window is displayed. Specify the IP addresses and subnets that contain the devices to be discovered:
a. Under Partial Discovery, select the required nodes and subnets.
b. To add a new subnet or node, click New.
c. Complete the fields as follows and click OK:
Rediscover
Select one of the following options:
IP Address
Type the required IP address.
Subnet
Type the required subnet and specify the number of netmask bits. The Netmask field is automatically updated.
d. To add new scope zones, click Scope.
e. To add a new discovery scope zone click New . To edit an existing scope zone, click the required entry in the list.
f. Complete the fields as follows and click OK:
Scope By:
Select one of the following options:
Subnet
Type the required subnet and specify the number of netmask bits. The Netmask field is automatically updated.
You can specify a subnet or an individual IP address using these fields.
v For example, to specify a Class C subnet 10.30.2.0, type 10.30.2.0/24, where 10.30.2.0 is the subnet prefix, and 24is the subnet mask.
v To specify an individual device, type an IP address and a subnet mask of 32. For example, type 10.30.1.20/32.
Wildcard
Use an asterisk (*) as a wildcard.
For example, to specify a scope of all IP addresses that begin with the 10.30.200. subnet prefix, type 10.30.200.*.
Restriction: Network Manager does not support the IPv4–mapped IPv6 format and expects all IPv6 addresses to be in standard colon-separated IPv6 format. For example, Network Manager does not support an IPv4–mapped IPv6 address such as
::ffff:192.0.2.128. Instead enter this address as ::ffff:c000:280 (standard colon-separated IPv6 format).
Protocol
Select the required Internet protocol: IPv4 or IPv6.
Action
Define the subnet range as an inclusion zone or exclusion zone. If the subnet range is an inclusion zone that you intend to ping during the discovery, click Add to Ping Seed List. Clicking this option automatically adds the devices in the scope zone as a discovery seed devices.
Restriction: The Add to Ping Seed List option is not available for IPv6 scope zones. This prevents ping sweeping of IPv6 subnets, which can potentially contain billions of devices to be pinged. Ping sweeping of IPv6 subnets can therefore result in a non-terminating discovery.
g. Click OK then click Go. When a full or partial discovery is running, the Start Discoverybutton is toggled off .
4. To stop a discovery, click Stop Discovery . The discovery might take a short time to stop, during which time both the Start Discovery and Stop Discoverybuttons are toggled off. If you stop a discovery, you cannot then do a partial discovery until after the next full discovery.
Note: When you stop a discovery, the discovery cache is lost. This is why you must wait for the completion of the next full discovery before being able to perform a partial discovery. It is possible to configure the Discovery engine to save the discovery cache as the discovery is running, which would enable you to run a partial discovery immediately following the manual stop of a
discovery. You can configure the Discovery engine to save the discovery cache by clicking Enabling Caching of Discovery Tables in the Advanced tab.
While the discovery is running, you can monitor the progress of the discovery.
After the discovery is complete, the Start Discovery button is toggled on, and you can run another full or partial discovery at any time. If the Event Gateway Disco plug-in is enabled, then a new discovery can be triggered automatically when a reboot event (event ID of NmosSnmpReboot triggered by the rebootDetection poll policy) is received.
Related concepts:
“About types of discovery” on page 1
Different terms are used to describe network discovery, depending on what is being discovered and how the discovery has been configured. You can run discoveries, rediscoveries, full and partial discoveries, and you can set up automatic discovery.
Related tasks:
“Monitoring network discovery from the GUI” on page 131
From the Active Discovery Status page, you can monitor the status and progress of the current discovery, investigate the work of the discovery agents, and view details of the last discovery.
“Starting partial discovery from the GUI” on page 158
Starting a partial discovery involves defining a seed and scopes.
“Troubleshooting an idle discovery” on page 168
If you start the discovery, and after some minutes no devices have been discovered, follow these troubleshooting steps.