How to Discover Devices
The Discover window provides two kinds of discover operations:
- IP Range Discover -- performs a discover based on one or more IP address ranges. An IP Range Discover discovers all devices within the specified IP address range(s).
- CDP Seed IP Discover -- performs discover operations of CDP-compliant devices in the network, starting with a one or more CDP seed devices.
Deciding what type of discover to use depends on your specific network configuration. Generally, if your network has all CDP-compliant devices that are configured with the same SNMP access parameters, the CDP Seed IP Discover is recommended. If your network has no CDP-compliant devices, or a mix of CDP and non-CDP-compliant devices, the IP Range Discover is recommended.
| TIP: | To discover a network with both CDP-compliant and
non-CDP-compliant devices, you can either perform an IP Range
Discover, or perform a CDP Seed IP Discover to first discover all the CDP-compliant devices,
and then perform an IP Range discover or use Add Device to add the
non-CDP-compliant devices. |
|---|
You can specify Discover options using the Discover view of the Options window (Tools > Options). Discover options include setting the timeout value (how long Discover waits before re-trying to contact a device), and the number of IP addresses Discover will try to contact simultaneously.
There may be an occasion when you want to add a device to the NetSight database without using a discover process. For example, you may want to monitor and manage one specific device for testing purposes. In that case, you would add a device using the Add Device Window.
Configuring Ping for Linux and Mac OS X Clients
The first time you run a Ping Only Discover from a Mac OS X or Linux client, the Discover will fail because jping is not executable. To fix this problem, perform the following steps to give the jping executable root privileges, allowing it to open up a socket for communication back to a NetSight client.
On a Linux client (32-bit or 64-bit):
- Open an xterm where you are logged in as root.
- mkdir -p /var/Extreme_Networks/NetSight
- cp ~/NetSight/System/<.bin32 or .bin64>/jping /var/Extreme_Networks/NetSight
- chmod a+x /var/Extreme_Networks/NetSight/jping
- chmod u+s /var/Extreme_Networks/NetSight/jping
On a Mac OS X client (64-bit):
- Open a terminal window.
- cd ~/NetSight/System/.bin64
- sudo chown root jping
IP Range Discover
Use the IP Range Discover to perform a discover based on one or more IP address ranges. The results of the discover process are displayed in the Discover Results table. You can then save the discovered devices to the NetSight database where they are displayed in the left-panel tree.
- Select Tools > Discover from the menu bar or click the
Discover button
in the
toolbar. The Discover window opens.
- Select the IP Range tab.
- At the top of the tab is a table where you specify the IP address
ranges. Each row defines a single range. When you first open the tab, a
default range is displayed based on the IP address of the Console
workstation.
NOTE: Use Console's table options and tools to filter, find, sort, print, and export information in the table, and to customize table settings. You can access these Table Tools through a right mouse click on a column heading or anywhere in the table body. For more information, see the Table Tools Help topic. - To add a new range, right-click on an existing row and select Insert Row. A new row will be created above the selected row using the same parameters. (Using your keyboard's down arrow or tabbing past the last row will also create a new row.) The position of a row determines the range's Precedence, as indicated in the second column. Precedence determines which parameters will be used if a device is in more than one range (the lower number yields higher precedence). For example, if a device is in two ranges -- one range with a precedence of 1 using an SNMPv3 profile, and one range with a precedence of 2 using an SNMPv1 profile -- the device will be saved with the SNMPv3 profile because that range has the higher precedence.
- To edit a range, simply tab
through the parameters and either enter a new value or use the
drop-down list to select a value.
- Enabled -- Select the checkbox to enable Discover for this IP address range. Only enabled ranges are searched when a discover operation is performed.
- Start IP -- Enter the IP address at which the range should begin.
- End IP -- Enter the IP address at which the range should end.
- Profile -- Use the drop-down list to select the access Profile that will give the Discover tool read access to the devices you want to discover. Ping Only allows discovering devices such as workstations and other devices that are not configured for SNMP. If Ping Only is selected, the Poll Type must be set to Ping. (See the Configuring Ping for Linux and Mac OS X Clients section above.) Click the Profile Details button to open the Authorization/Device Access Window - Profiles/Credentials Tab where you can create and edit Console profiles. If you discover an existing device using a different profile than the device is already using in the database, saving the device will overwrite the profile currently being used in the database.
- Context -- SNMP Context lets you specify a context that has been configured on a device. The context lets you access a subset of MIB objects related to that context. Console lets you specify a SNMP Context for both SNMPv1/v2 and SNMPv3.
The use of context differs depending on the protocol version being used with the credentials used by the selected Profile:
- When used, with SNMPv3 credentials, the context provides access to a specific collection of MIB objects associated with a particular context configured on the device. If the credentials used are accepted, but the context specified doesn't match one configured on the device, access is denied.
- Some devices also provide limited support of contexts for SNMPv1/v2. For these devices, a SNMPv1 or SNMPv2 credential (community name) can be mapped, through Local Management, to a particular SNMP context on the device. Thus, when SNMPv1/v2 credentials are used with a Context entry, access is granted to the subset of MIB objects associated with that context. If the credential used is accepted, but the context specified doesn't match a context configured on the device, access is granted to the default context.
Console treats each context for a given device (IP address) as a distinct device. All SNMP contexts known to the device can be displayed using the show snmp context command. Refer to your device Configuration Guide for more information about setting and showing SNMP contexts.
- Poll Type -- Use the drop-down list to select the Poll
Type used to discover devices: SNMP, Ping or Not Polled. When SNMP
is specified, the SNMP version (SNMPv1 or SNMPv3) is determined by the
Profile specified for the IP Range. If the Profile is set to Ping Only, the Poll Type must be set to Ping. If you discover an existing device using a
different poll type than the device is already using in the database,
saving the device will overwrite the poll type currently being used
in the database.
NOTE: On a Windows platform, device operational status cannot be determined for devices with their Poll Type set to Ping unless you are logged on and running Console as a user with Administrative privileges. - Poll Group -- Use the drop-down list to select a Poll Group for the discovered
devices. Console provides three distinct poll groups (defined in the
Status Polling view of the
Suite-Wide Options window) that each specify a unique poll frequency. When you
save newly discovered devices to the database, they will be polled
with the poll group specified here. If you save discovered devices
that already exist in the database, the poll group specified here
will overwrite the poll group currently being used in the database.
NOTE: If a Poll Type of "Not Polled" is specified, the Poll Group will only be used if/when the Poll Type is changed to SNMP or Ping. - Vendor -- Use the drop-down list to specify whether you want to discover all devices or only Extreme devices.
- Click Discover to begin the discover operation. Discovered devices are listed in the
Discover Results table. The progress of each
range discover is displayed as a
percentage in the corresponding Progress column.
NOTE: When a Discover operation is initiated, all rows that are enabled are checked for validity. If any rows have invalid parameters, the Progress column for that row will alert you to the invalid entry. - After the discover is complete you can save all or selected devices to the database:
- Click Save All to save all the discovered devices to the NetSight database.
- Use the Hide Duplicate and Empty MACs checkbox to filter the Discover Results table to show one discovered device per MAC address. (When routed interfaces cause the same device to be discovered multiple times, this checkbox filters out duplicate entries.) Click Save to save the filtered devices to the database.
- Select only the desired devices in the Discovered Devices table and click Save to save those devices to the database.
- Select all or some of the devices and right click one of the selected devices and select Add Devices to Group to open a window where you can select a specific group where the devices will be saved.
To remove a device from the table, select the device and click Remove.
NOTE: If the IP Range includes broadcast addresses (.0, .255, .127, .128, depending on the subnet mask), the addresses may be discovered as devices. To make the polling of devices in the Console tree as efficient as possible, these addresses should be removed and not saved to the database.
It is recommended that you backup the NetSight database (Tools > Server Information > Database Tab) after you have saved your discovered devices. - To delete an IP range, right-click on the table row and select Delete Row. You can select and delete multiple rows.
| TIP: | Specify as narrow an IP address range as possible. The wider the
range, the longer it will take to perform the discover. For example, if you
are discovering IP addresses 111.111.111.20 through 30, and 111.111.111.240
through 250, it is faster to create two separate discovers for each range rather
than performing one discover for 111.111.111.20 through 250. |
|---|
CDP Seed IP Discover
Use the Discover window to perform a discover for CDP-compliant devices in the network. The results of the discover process are displayed in the Discover Results table. You can then save the discovered devices to the NetSight database where they are displayed in the left-panel tree.
- Select Tools > Discover in the menu bar or click the
Discover button
in the
toolbar. The Discover window opens.
- Select the CDP Seed IP tab. You can define multiple CDP Seed discover operations in the view. Define each discover operation in a separate row.
To add a new range, right-click on an existing row and select Insert Row. A new row will be created above the selected row using the same parameters. (Using your keyboard's down arrow or tabbing past the last row will also create a new row.) The position of a row determines the Precedence, as indicated in the second column. Precedence determines which parameters will be used if a device can be discovered by the parameters in than one row (the lower number yields higher precedence). For example, if a device could be discovered by two discover operations -- one with a precedence of 1 using an SNMPv3 profile, and the other with a precedence of 2 using an SNMPv1 profile -- the device will be saved with the SNMPv3 profile because that range has the higher precedence. - To edit a row, simply tab through the parameters and either enter a new value or use the drop-down list to select a value.
- In the Seed IP column, enter the IP address for your CDP seed device. Discover will use the seed device's CDP Neighbor Table to begin discovering all CDP-compliant devices.
- Use the drop-down list in the Profile column to select the access Profile that will give the Discover tool read access to the devices you wish to discover. Click the Profile Details button to open the Authorization/Device Access Window - Profiles/Credentials Tab where you can create and edit Console profiles. If you discover an existing device using a different profile than the device is already using in the database, saving the device will overwrite the profile currently being used in the database.
- Use the drop-down list to select the Poll Type used to discover devices: SNMP, Ping or Not Polled. When SNMP is specified, the SNMP version (SNMPv1 or SNMPv3) is determined by the Profile specified for the IP Range. If the Profile is set to Ping Only, the Poll Type must be set to Ping.
(See the note above about Ping Only Discovers.) If you discover an existing device using a different poll type than the device is already using in the database, saving the device will overwrite the poll type currently being used in the database.
NOTE: On a Windows platform, device operational status cannot be determined for devices with their Poll Type set to Ping unless you are logged on and running Console as a user with Administrative privileges. - Use the drop-down list to select a Poll Group for the discovered devices. Console provides three distinct poll groups (defined in the Status Polling view of the Suite-Wide Options window) that each specify a unique poll frequency. When you save newly discovered devices to the database, they will be polled with the poll group specified here. If you save discovered devices that already exist in the database, the poll group specified here will overwrite the poll group currently being used in the database.
NOTE: If a Poll Type of "Not Polled" is specified, the Poll Group will only be used if/when the Poll Type is changed to SNMP or Ping. - Click Discover. Discovered devices are listed in the Discover
Results table.
NOTE: If CDP is not enabled on a seed device, a message is displayed, asking if you would like to enable CDP. Yes enables CDP in the device, waits for 30 seconds, then continues with the discovery. No cancels discovery using that seed device. - After the discover is complete you can save all or selected devices to the database:
- Click Save All to save all the discovered devices to the NetSight database.
- Use the Hide Duplicate and Empty MACs checkbox to filter the Discover Results table to show one discovered device per MAC address. (When routed interfaces cause the same device to be discovered multiple times, this checkbox filters out duplicate entries.) Click Save to save the filtered devices to the database.
- Select only the desired devices in the Discovered Devices table and click Save to save those devices to the database.
- Select all or some of the devices and right click one of the selected devices and select Add Devices to a Group to open a window where you can select a specific group where the devices will be saved.
To remove a device from the table, select the device and click Remove.
NOTE: It is recommended that you backup the NetSight database (Tools > Server Information > Database Tab) after you have saved your discovered devices.
For information on related windows:
For information on related tasks:
