Connectivity Guide

Table 13. ROOT
CCITT(0)
ISO(1)
ORG(3)
DOD(6)
INTERNET(1)
MGMT(2)
MIB(1)
EXPERIMENTAL(
3)
PRIVATE(4)
ENTERPRISES(1)
DELL (674)
SNMPv2(6)
In the preceding example, the OID prex 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-dened 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 congured at each
SNMP agent and is passed as a part of all SNMP request messages. There is no verication that the requester is actually a member of the
specied community. As most system and network management data is not condential, 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 o a system,
recongure 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 conguration 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.
NOTE: As of iDRAC7 rmware release r1.30.30, iDRAC7 supports SNMP query operations (GET, GETNEXT, GETBULK) via the
SNMPv3 protocol, in addition to supporting query operations via the SNMP v1 and SNMP v2c protocols. More specically,
iDRAC7 now supports the SNMP User Security Model (USM).
SNMP Traps
SNMP is frequently used to monitor systems for fault conditions such as temperature violations, hard drive failures. Management
applications can monitor for these conditions by polling the appropriate OIDs with the Get command and analyzing the returned data. This
method has its drawbacks. If it is done frequently, signicant amounts of network bandwidth can be consumed. If it is done infrequently,
the response to the fault condition may not occur in a timely fashion. SNMP traps avoid these limitations of the polling method.
An SNMP trap is an asynchronous event indicating that something signicant has occurred. This is analogous to a pager receiving an
important message, except that the SNMP trap frequently contains all the information needed to diagnose a fault.
16
Introduction