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The Cisco EMF Auto Discovery application allows you to examine the network for IP and SNMP devices and create a managed object for each new device discovered. Auto Discovery can be opened from the Cisco EMF Launchpad window or from a pop up menu available on a selected object.
The Auto Discovery application can use three different mechanisms for discovering devices:
The Auto Discovery application can discover devices on more than one subnetwork by using multi-hop discovery. This option is available when using SNMP or IP and SNMP discovery. When Cisco EMF discovers a device that is connected to more than one network, it can run Auto Discovery on the next network. It does this if the hop count is greater than zero. The next network is then discovered with hop count minus one.
When Auto Discovery is launched as a service from a selected IP manageable object, the discovery range, by default, is related to the IP address of the launch object.
An option is available to specify the physical location where discovered objects will be created. This is particularly useful when using Auto Discovery with Element Managers.
You can configure Auto Discovery to be scheduled as described in the "Scheduling Auto Discovery" section.
The following information is necessary to carry out Auto Discovery:
Auto Discovery proceeds with IP pings (ICMP echo requests) first (if IP is selected), followed by SNMP GETs of sysDescr and sysObjectId (if the ping was successful and SNMP is selected or SNMP only is selected).
Only devices within the selected range should be pinged, unless however, one of the devices discovered is a router. For example, if a router has three ports with IP addresses 172.23.145.10, 130.159.72.40, and 142.123.45.200, the system automatically pulls the network address entry table and creates network objects for the networks on the other interfaces. As Cisco EMF is discovering on network 172.23.145.0, it finds the first interface. It also finds that the device is a router (it has IP forwarding configured), so it finds the other interfaces and creates networks for 130.159.72.0 and 142.123.45.0, as well.
The hop count field specifies how many times auto discovery should begin on a new subnet. If Cisco EMF discovers a device with multiple IP interfaces, it automatically starts auto discovery on the other interfaces if the hop count is greater than zero; the address range is the entire subnet for that interface and the hop count is decremented each time this occurs.
If no response to the ping is received within the timeout period, the operation is tried again, up to the number of times specified in ping retries.
For SNMP gets, all provided community strings are tried until one succeeds or the list is exhausted.
The Auto Discovery application is launched using the 
icon in the Cisco EMF Launchpad window or
from other Cisco EMF applications. Select the Auto Discovery option from the pop up menu available when you right click on a selected object. A window similar to Figure 5-1 is displayed.
To discover IP devices, proceed as follows:
Step 1 Select the object within the Map Viewer window that Auto Discovery will be launched from.
Step 2 Open the Discover Network Devices window (refer to Figure 5-1).
The object name and address are displayed in the Discovery Configuration panel of the window.
Step 3 Select the drop down list next to Discovery Method and select IP from the displayed list.
IP is displayed next to Discovery Method.
Step 6 To start the discovery process, select the device from the Device Interfaces list, then click the Start button.
The Discovery Progress window is displayed. The Action Log displays the auto discovery progress in a tabular format. A window similar to Figure 5-4 is displayed.
When all the relevant IP devices on the network have been discovered, an object class is created and stored under the Network view for each device. These devices can then be accessed by the Map Viewer.
To discover SNMP devices or IP and SNMP devices, proceed as follows:
Step 1 Select the object within Map Viewer that Auto Discovery will be launched from. From the pop up menu, select Auto Discovery, or launch the Auto Discovery application from the Cisco EMF Launchpad.
Step 2 Open the Discover Network Devices window.
The object name and address are displayed in the Discovery Configuration section of the window.
Step 3 Select the drop down list next to Discovery Method, then select SNMP or IP & SNMP from the displayed list.
SNMP or IP & SNMP is displayed next to Discovery Method.
Step 4 Set the hop count to the number of subsequent devices you want to discover away from the starting network. The maximum number is 16.
Step 5 For IP devices, in the Ping Retries data entry box, specify the number of times the system should try to identify whether an active machine is connected at a specified IP address. The maximum number is 10.
Step 6 Enter a community name in the New Community data entry box, then click the Add button. The new community name is displayed along with all of the other community names already entered.
Step 7 In the data entry box next to SNMP Retries, enter the number of times the system should try to communicate with a device without receiving an expected reply, before it is discarded as not being an SNMP device. The maximum number is 10.
Step 8 In the Physical Location panel, click the Use Physical Path button. Make sure the correct path is shown. Select Get Path, then select the correct Physical View if required.
Objects available for selection have an associated green color box. A red color box next to a node indicates the object is not available.
Step 9 In the data entry box next to SNMP Timeout, enter the required time. The default is set to 10 seconds.
Step 10 To start the discovery process, click the Start button.
The Discovery Progress window is displayed.
The Action Log displays the auto discovery progress and displays the results in tabular form. A window similar to Figure 5-4 is displayed.
When all of the relevant devices on the network have been discovered, an object class is created and stored under the Network view for each device.
The IP address field of the discovery configuration window is editable. To add a new address range to the interfaces list, edit the ipAddress fields. Enter the address of any device within the network range you wish to discover by selecting the first field of the ipAddress and entering the IP Address, then press either Tab or Enter to move onto the next part of the ipAddress.
When you exit from the last part of the ipAddress field (by pressing Tab or Enter), a new address range is added to the interface list. The address range is automatically calculated using the class of the IP address entered (class A, class B, or class C).
To remove an address range from the interfaces list, select the interface, then press the Backspace key.
The Action Log displays the auto discovery progress and its results. A window similar to Figure 5-4 is displayed.
The Discovery Progress window displays the progress of the auto discovery process in two ways. The Device Data panel displays information on the number of devices found and information on the success of IP and SNMP queries performed on the devices. The data is presented in a spreadsheet format with each row representing a subnet being discovered. This provides an indication of the current state of the auto discovery process. Each cell has an accumulating total indicating the current number of:
The Action log provides information on which networks are being discovered, when they are finished, when devices are created, and when the entire auto discovery process is complete.
Auto Discovery can be automatically scheduled by editing the discoverySchedules file in the <CEMF_ROOT>/config/discoverySchedules directory, where <CEMF_ROOT> is the CEMF installation directory. This allows you to specify the IP address range, communities to query within that network, the number of hops, the number of ping and SNMP retries, the discovery method, and time and period values.
Step 1 Using a text editor, open the discoverySchedules file.
A file similar to the following example appears:
# # DiscoveryMethod 0 = IP only, 1 = SNMP only, 2 = IP and SNMP # schedules = sched1, sched2 sched1StartAddress = 194.131.185.1 sched1EndAddress = 194.131.185.254 sched1Communities = public, private sched1Hops = 0 sched1PingRetries = 0 sched1SnmpRetries = 0 sched1DiscoveryMethod = 2 sched1SnmpTimeout = 10 sched1StartTime = 14:09:00 sched1Period = 5 minutes sched1ParentPath = physContainment:/testObject1/ sched2StartAddress = 194.131.3.1 sched2EndAddress = 194.131.3.254 sched2Communities = public, private sched2Hops = 0 sched2PingRetries = 0 sched2SnmpRetries = 0 sched2DiscoveryMethod = 2 sched2SnmpTimeout = 10 sched2StartTime = 11:30:00 sched2Period = 7 days sched2ParentPath = physContainment:/SITE-1/
This example shows schedules for two networks. You can edit existing schedules or create new schedules as required. For example, to create a schedule for a third network you would create entries in the file with sched3 preceding each line.
Step 2 The StartAddress and EndAddress specify the network you want to auto discover. Enter the appropriate IP addresses.
Step 3 In Communities, enter the relevant SNMP community names, in a comma separated list.
Step 4 Enter the number of hops. This is a value between 0 and 16. The hop count should be left at zero when Auto Discovery using IP only is selected.
Step 5 Enter the number of ping retries. This is a value between 0 and 10.
Step 6 Enter the number of SNMP retries. This is a value between 0 and 10.
The Discovery Method options are as follows:
(a) IP only
(b) SNMP only
(c) IP & SNMP
Step 7 Enter the start time, using the 24 hour clock notation.
The period can be defined by a number and a keyword (minutes or hours or days.)
Step 8 When all changes have been made, save the files and close the text editor. Run the files using the <CEMF_ROOT>/bin/reinit_discovery_scheduler program.
Posted: Fri Jan 7 15:20:55 PST 2000
Copyright 2000©Cisco Systems Inc.
