Installation manual

58
Disabled Mode
This mode disables the operation of the ATTO SNMP
agent. Any network ports it has open to support SNMP
are closed, making it inaccessible to any Management
Station. The system service will not forward requests
to it, and no TRAPs are sent out when events occur.
Basic Setup
The ATTO SNMP agent can be configured through the
SNMP tab on the localhost node. When you first enter
the SNMP tab, and until you commit a new mode, the
SNMP mode will be
Disabled . The various settings
can be manually edited, but the simplest way to enable
SNMP support in this case is to click the
Default
button and then click
Commit . This will load the proper
settings based on your current system configuration,
and then reconfigure the agent to use them. The
operational mode (enabled or subagent) and port will
be selected based upon whether or not an operating
system SNMP service is running.
Note
The System Service and TRAP Service
states are not updated dynamically as they
change in the system. They can be manually
updated at any time by clicking
Refresh .
Note
In order to properly secure access to the
agent from the local machine, it is suggested
to change the default string in the
Communities list before committing the
default settings.
This basic setup will allow you to browse the
information that is made available by the agent with a
3rd party application, but will not send out TRAPs.
TRAP destinations are network specific, and cannot
be determined programmatically.
Configuration Options
Agent Port
This value specifies the UDP port that the ATTO
SNMP agent listens on for incoming Management
Station requests. The port cannot be used by any other
process on the system, or the behavior of both the
agent and the other process is undefined. The
standard port value for SNMP is 161, but that is not the
default value in subagent mode, because it is
assumed that the system service is using that port.
Note
A binding error may not occur if the port is
already in use. If you are not sure if a port is
in use, use the netstat command.
In enabled mode, this is the port the Management
Station uses to communicate with the agent. In
subagent mode however, the agent will
not respond
on this port to Management Station requests from a
different machine. The port the Management Station
needs to use is the system service's port.
Communities
This is a list of community strings accepted by the
agent when it receives an incoming request. If a
Management Station makes a request and provides a
community string that is not in this list, the request is
dropped by the agent. If authentication traps are
enabled, one will be sent to each configured
destination. The list can be manipulated through the
Add, Edit and Remove buttons below it. An existing
community must be selected to edit or remove it. A
valid community string has a length between 1 and
128 (inclusive) and can include any keyboard
character.
Note
In subagent mode, only a single community
can be specified since that is the community
used by the Master Agent when talking to the
ATTO SNMP subagent. The communities
that Management Stations must use are
configured through the system service.
Note
For added security in subagent mode, you
should change the default community string.
The agent cannot tell the difference between
a local Management Station request and a
request from the system service, which
means a local user can bypass the
authentication checks done by the system
service if they know this community string
and the agent's port.