Allied Telesis AT-S63 User Manual

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Chapter 3: SNMPv1 and SNMPv2c
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Section I: Basic Operations
Community String Attributes
A community string has attributes for controlling who can use the string 
and what the string will allow a network management to do on the switch. 
The community string attributes are defined below:
Community
String Name
A community string must have a name of one to eight alphanumeric 
characters. Spaces are allowed.
Access Mode
This attribute defines the permissions of a community string. There are 
two access modes: Read and Read/Write. A community string with an 
access mode of Read can only be used to view but not change the MIB 
objects on a switch. A community string with a Read/Write access can be 
used to both view the MIB objects and change them.
Operating Status
A community string can be enabled or disabled. When disabled, no one 
can use it to access the switch. You might disable a community string if 
you suspect someone is using it for unauthorized access to the device. 
When a community string is enabled, then it is available for use.
Open or Closed
Access Status
This feature controls which management stations on your network can use 
a community string. An open access status permits any network manager 
who knows the community string to use it. A closed access status restricts 
the string to those network managers who work at particular workstations, 
identified by their IP addresses. You specify the workstations by assigning 
the IP addresses of the workstations to the community string. A closed 
community string can have up to eight IP addresses of management 
workstations.
If you decide to activate SNMP management on the switch, it is a good 
idea to assign a closed status to all community strings that have a Read/
Write access mode and then assign the IP addresses of your 
management workstations to those strings. This helps reduce the chance 
of someone gaining management access to a switch through a community 
string and making unauthorized configuration changes.
Trap Receivers
A trap is a signal sent to one or more management workstations by the 
switch to indicate the occurrence of a particular operating event on the 
device. There are numerous operating events that can trigger a trap. For 
instance, resetting the switch or the failure of a cooling fan are two 
examples of occurrences that cause a switch to send a trap to the 
management workstations. You can use traps to monitor activities on the 
switch.
Trap receivers are the devices, typically management workstations or 
servers, that you want to receive the traps sent by the switch. You specify 
the trap receivers by their IP addresses. You assign the IP addresses to