How does NNM Determine a Node's hostname, selection name and the label?

  • Document ID:KM65448
  • Creation Date:15-Jun-1999
  • Modified Date:21-Dec-2011
    • Micro Focus Products:
      network node manager

Summary

How does NNM Determine a Node's hostname, selection name and the label?

Question

How does NNM Determine a Node's hostname, selection name and the label?

Answer

The following applies to NNM releases:

4.1X (starting with the March 1997 consolidated patch (HPUX 10.X: PHSS_10339, HPUX 9.X: PHSS_10338, Solaris: PSOV_1452)) and greater. References to IPX apply only to releases 5.0 and greater.

It is important to draw the distinction between names and labels. Names are things that must be unique in the object (ovwdb) and topology (ovtopmd) databases. In NNM, nodes have two kinds of names: IP Hostnames and Selection Names. Labels are the strings that show up on the node in a map.

IP Hostnames are determined in NNM by applying the following rules, in order:

  1. If the node supports IP:
    • If a non-migratable software loopback IP address (other than 127.0.0.1) exists on the node, and the address resolves to an IP hostname, that hostname is used.
    • Otherwise, NNM chooses the name associated with the lowest numbered non-migratable IP address that resolves to an IP hostname.
    • If no IP addresses resolve to an IP hostname, the lowest numbered non-migratable IP address is formatted as a string and used as the hostname.

      [ "lowest numbered" means when compared as integers. ]
      [ "non-migratable" applies only to HP's Service Guard
      nodes; a migratable address is one that can migrate between
      systems in a Service Guard cluster. ]

  2. Otherwise, if the node supports IPX:
    • If the node has an internal IPX server address (i.e. an address of the form <netnum 000000000001), that address is formatted as a string and used as the hostname.
    • Otherwise, the lowest numbered IPX address is formatted as a string and used as the hostname.

      [ "lowest numbered" is determined by a byte-by-byte comparison ]

  3. Otherwise, if the node supports neither IP nor IPX, but has an LLA/MAC address, the address is formatted as a string and used as the hostname.

    The hostname is stored in the object database "IP Hostname" field, making the name somewhat of a mis-nomer (it could be an IPX name). For interfaces, separate IP and IPX address fields exist.

Node selection names are by default the same as the IP Hostname, though users and applications can change the selection name. If the selection names for two objects conflict, a numeric ID string is appended to one of the selection names in order to achieve uniqueness.

For node labels the rules are (applied in order):

  1. If the node has an IP hostname (see 1a and 1b under names above), then the label is the IP hostname truncated to just the basename.
  2. Otherwise, if the node is a NetWare server:
    • If the node has a NetWare Server Name, it is used as the label.
    • Otherwise, the label is the network number of the internal Server address (i.e. the 000000000001, which is the same for every server, is removed).
  3. Otherwise, if the node supports SNMP and reports a SNMP sysName value, that value is used as the label (NNM 5.0X only).
  4. Otherwise, if the node supports IP, an IP address is used as the label (see 1c in the "names" section).
  5. Otherwise, if the node supports IPX, the host-address portion of the IPX address is used as the label. The address is formatted to translate the vendor of the hardware. (E.g. 100:080009ABCDEF gets a label of "HP-ABCDEF").
  6. Otherwise, if the node has a LLA/MAC, the physaddr formatting as described in (5) is performed and the result is used as the label.