HP Network Node Manager 9 : Discovering and Monitoring Your Network - Examining discovery results (part 3)

Discovery examples

Here, we provide few real life examples which may be familiar to you.

Example 1: Seed module

Assume that we have a network that has to be managed. We have the IP addresses of all devices that need to be managed, and our network is stable. New devices are rarely installed and we have control over them.

According to such requirements, the fastest and most accurate way would be to seed all devices for discovery, as shown in the diagram below:

When seeding a list of nodes that need to be discovered, we make sure that we load all nodes we need to, and which make our discovery configuration more simple. If you have a list of nodes and it's more than few nodes, you'd rather load seeds from the file using the nnmloadseeds.ovpl command. The previously mentioned filter configuration example provides steps on how to configure seeds using the batch file.

Example 2: Discover by IP address range and system Object ID

An ISP network consists of three networks: backbone, distribution, and access network. The ISP only wants to monitor the backbone and distribution networks, with only few devices from the access network, which have a specific service level agreement with customers. The backbone consists only of Cisco routers; the distribution network uses only Cisco equipment. Both networks have strictly dedicated IP address ranges. The access network has many vendors' equipment and NOC staff has the IP addresses of the devices, which have a specific service level agreement (VIP customers).

The following is a network diagram:

In this case, one of solutions to create discovery could be achieved by creating the following discovery rules:

• Devices that have SNMP system object ID .1.3.6.1.4.1.9... and are from following IP address range.

  The following diagram represents Auto-discovery by system object ID:

  
• Seed GOLD SLA devices (VIP): This would assure that you don't miss any device from your VIP list.

  The following diagram represents Auto-discovery by IP addresses:

  

Now you need to wait for a couple of minutes to see the discovery results. If the number of devices which need to pass the discovery filter is large, you may need to wait for more than a couple of minutes.

If you don't see some of the nodes even after waiting for a long time, try the following:

• Review your discovery filter and make sure you didn't miss anything
• Make sure these nodes are configured for SNMP and NNMi has that SNMP community set in Communication Configuration view
• If you are sure you did the previous steps correctly, you can enter node (nodes) into seed

Rediscovering your network from scratch

Sometimes, when your discovered network looks far from what you expected, it is easier to wipe the whole NNMi database and start discovery from scratch. It is very common during implementation, when the initial discovery filters don't work as they were supposed to.

If you decide to delete existing NNMi inventory and start discovery all over again, you should proceed with following steps:

1. Stop NNMi services:

   ovstop -c
   

2. Optional: Backup existing database:

   nnmbackup.ovpl -type offline -target <backup_directory>
   

3. Optional: Save current NNMi configuration (exports into XML file):

   nnmconfigexport.ovpl
   

4. Optional: Save existing incidents:

   nnmtrimincidents.ovpl
   

5. Drop and create the NNMi database from scratch:

   nnmresetembdb.ovpl -nostart
   

   Tip

   For an Oracle database, the database should be dropped using Oracle native tools or commands.

6. If you have iSPIs installed, or third party application integration, follow this product integration documentation to check whether some additional actions should be taken.
7. Start NNMi services:

   ovstart -c
   

8. Start NNMi configuration and discovery.