System information

388 Observer Suite: SNMP Management
Be careful to use the proper type of value when setting the value. If you
attempt to set an integer SNMP value to a character string (e.g., ”Bob”) it will
be set to zero.
5. If the attempt to set the value fails, an error dialog will be displayed, and the Status
line on the Set Value dialog box will read “Failed” instead of “Done.”
Failure can happen for one or both of two reasons:
• the MIB object you are attempting to set is read-only and cannot be reset,
and/or
• you do not have the proper read-write community name for this device.
SNMP Technical Overview
History
Simple Network Management Protocol (SNMP) was proposed in 1988 as a set of
Requests for Comments (RFCs) defining the basic principles and implementation for a
protocol that would establish a standard for Internet monitoring and management, as a
replacement for the myriad of vendor-specific network management solutions available at
the time.
Since then, SNMP has gained considerable popularity. Although it hasn’t replaced all
proprietary solutions, it has become a widely accepted standard for network management.
Subsequent RFCs for SNMP have corrected problems and supplemented the original
standard Management Information Base (MIB).
The standard MIB, defined by RFC1213, defines numerous objects in ten groups—
system, interfaces, address translation, IP, ICMP, TCP, UDP, EGP, transmission, and
SNMP.
However, manufacturers are constantly adding capabilities to their products, and some of
them are not covered by the standard objects and groups. To bring the benefits of SNMP
monitoring and control to additional features, software and hardware vendors have
developed proprietary MIBs.
Most major computer hardware manufacturers now offer lines of networking products that
support SNMP, including network cards, hubs, bridges, routers, switches, and printers.
Because adding an SNMP agent to network hardware often increases the price of the
product, manufacturers usually offer versions with and without SNMP support.
Most operating systems, including UNIX and Microsoft Windows systems, implement
SNMP agents in their architecture.
In early 1990, the original SNMP specifications were revised and updated. New MIB
groups were added and some old MIB objects became obsolete. In general, the new MIB
specification, called MIB II (or MIB-2) is compatible with the original MIB, now called
MIB I.