components is called an OID prefix. The second difference is that OIDs support the concept of indexes or
keys. The OID prefix specifies the data class but does not specify an instance of the data within the class.
Indexes can be used to identify the instances of a data class. These indexes are referred to as the OID
suffix.
The assignment of values for each OID prefix component can be illustrated by using a tree structure. The
following is an example of an OID assignment:
Table 11. ROOT
CCITT(0)
ISO(1)
ORG(3)
DOD(6)
INTERNET(1)
MGMT(2)
MIB(1)
EXPERIMENT
AL(3)
PRIVATE(4)
ENTERPRISE
S(1)
DELL (674)
SNMPv2(6)
In the preceding example, the OID prefix for the Dell enterprise would be 1.3.6.1.4.1.674.
The numbers in boldface type show the categories and numbers that apply to Server Administrator. All
Server Administrator-defined OIDs consist of 1.3.6.1.4.1.674 followed by additional component values.
SNMP Security
SNMP version 1 has a very limited security mechanism. SNMP agents support the use of a community
string, which is configured at each SNMP agent and is passed as a part of all SNMP request messages.
There is no verification that the requester is actually a member of the specified community. As most
system and network management data is not confidential, this limited security is acceptable for Get types
of requests. On the other hand, this security is not acceptable for Set types of operations where an SNMP
request could power off a system, reconfigure a redundant array of independent disks (RAID) card, and so
on. Dell has chosen not to support SNMP Set operations for this reason.
NOTE: The default SNMP agent configuration usually includes a SNMP community name such as
public. For security reasons, change the SNMP community names from their default values. For
information about changing SNMP community names, see the Dell OpenManage Server
Administrator User’s Guide available on the Dell Support website at dell.com/openmanagemanuals.
17