System information

338 Observer Suite: SNMP Management
before deciding that the request was lost and the number of times SNMP Management
Console will resend the packet. When the maximum number of retries is reached and no
reply has been received, SNMP Management Console considers the SNMP agent not
present, out of order, or turned off, and displays a timed out message in the agent log.
Configuring SNMP Agents
For the SNMP Management Console to work with SNMP agents on the network, both
must be configured.
Here, the term “SNMP Agent” is used to mean the actual agent on the
network device, rather than the representation of that device in Observer’s
SNMP Extension.
The SNMP agents on the network must recognize SNMP Management Console as a
management station that is permitted to access their MIB information. To poll the agents
for information, the SNMP Management Console must know the IP addresses and
community names of each agent.
A device’s “community name” is, in effect, its password. Some devices have two
community names (or two passwords) one of which is a read-only password (usually
called the community name, the public community name, or the read community name),
and a read-write password (usually called the private community name, the write
community name, read/write community name, or sometimes, the community name). In
many environments, the default read community name is “public” and the default write
community name is “private.”
If there is a public and a private community name, SNMP Management Console can use
either, although it cannot write to an SNMP device without the read-write community
name.
The necessity of configuring the SNMP agent on the network will depend on the device.
Most devices, when properly queried using the appropriate community name, will
respond.
If you wish to restrict access to the SNMP device, replace “public” with a new
community name. The new community name becomes your password to the
agent.
The usual reason to change community names is for security. Security can
be enhanced by picking a random string of alphanumeric characters as a
community name, rather than using the default community name of “public,”
which provides little, if any, security at all.
Some agents will require further configuration, sometimes involving entering the SNMP
Management Console's IP address in the agent's database as a management console.
In such cases, the default IP address is 0.0.0.0. The “0” IP address means
that any SNMP management station can access the agent. If you decide that