Automatic Discovery

After a discovery, all nodes will probably not show the same level of information. (see Node Properties to check what information was found). The following paragraphs show a few reasons why some information could be missing.

• Missing node(s): You know one or more nodes exist, and they are not included in the map.
  Why: The node(s) are not alive at this moment; a firewall is blocking ICMP; the timeout used was too short. Uncheck the Ping Required option.
• Nodes with no DNS names
  Why: No information was retrieved from the DNS , WINS or a local HOST or LMHost file. Check that the DNS are properly configured in your TCP/IP configuration (IpConfig /All) and that the local files are ok.
• Nodes with no SNMP detected.
  Why: SNMP is not available on this node or you do have the correct community name.
• Nodes with no WMI detected.
  Why: WMI is not available on this node: not a Windows based node. You do not have access rights to this node: either get a correct account and password, or add the current user to the WMI security. Otherwise, there is a friewall blocking this protocol: this is the default on XP SP2 and later.
• Nodes no MAC address detected
  Why: NetworkView uses 4 different methods to discover MAC addresses. If no information is retrieved, the node is not on the local LAN, was not accessible with SNMP, WMI or NetBIOS.
• Nodes with no NetBIOS information
  Why: Not a Windows operating system, firewall blocking the access. No special security needed.
• Nodes with no TCP Port information
  Why: A firewall is blocking the access to the selected ports.
  As you can see from the above statements, firewalls are surely the most important reason why you cannot get correct data on your nodes. Then other important reason is wrong security credentials (WMI, SNMP).

If the type assigned during discover is wrong, you can easily modify the two MAC OUI and SNMP databases to permanently associate one of the built-in types with a specific OUI (first 6 digits of the MAC address) or a SNMP OID.

For all nodes, you can edit the DNS Name, the NetBIOS name and domain, the MAC address and its manufacturer, and the Type. for example by checking what was given by the TCP Ports.

You can also add a text note and add routes or routes labels manually.