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Chapter 21: Configuring SNMP
Configuring SNMP Traps
Psion Teklogix 9160 G2 Wireless Gateway User Manual 217
21.3.1 Configuring SNMP Traps
SNMP Traps facilitate asynchronous communication of messages from SNMP managed
devices (like the 9160 G2 Wireless Gateway) to designated hosts. If a Network Management
System (NMS) is responsible for monitoring a large number of devices on a network, it is
not practical to periodically query every device on the network. By enabling SNMP event
traps on the AP, individual devices can send messages directly to SNMP Managers or to
other designated hosts on the NMS regarding some network events, such as network inter-
faces going up or down, clients failing to associate or authenticate with the access point,
system power up or down and changes in the network topology.
Restrict the source of
SNMP requests to only
the designated hosts or
subnets
You can restrict the source of permitted SNMP requests.
• To restrict the source of permitted SNMP requests, click Enabled .
• To permit any source submitting an SNMP request, click Disabled .
Hostname or subnet of
Network Management
System Specify the DNS hostname or subnet of the machines that can execute GET and SET requests
to the managed devices.
As with community names, this provides a level of security on SNMP settings. The SNMP agent
will only accept requests from the hostname or subnet specified here.
To specify a subnet, enter one or more subnetwork address ranges in the form Address-
Range/MaskLength , where AddressRange is an IP address and MaskLength is the number of
mask bits. Both formats ‘NetAddress/NetMask’ and ‘NetAddress/MaskLength’ are supported.
Individual hosts can be provided for this, i.e. I.P Address or Hostname. For example, if you enter
a range of
192.168.1.0/24
this specifies a subnetwork with address
192.168.1.0
and a subnet mask of
255.255.255.0
.
The address range is used to specify the subnet of the designated NMS. Only machines with IP
addresses in this range are permitted to execute GET and SET requests on the managed device.
Given the example above, the machines with addresses from
192.168.1.1
through
192.168.1.254
can execute SNMP commands on the device. (The address identified by
suffix
.0
in a subnetwork range is always reserved for the subnet address, and the address iden-
tified by
.255
in the range is always reserved for the broadcast address).
As another example, if you enter a range of
10.10.1.128/25
, machines with IP addresses
from
10.10.1.129
through
10.10.1.254
can execute SNMP requests on managed
devices. In this example,
10.10.1.128
is the network address and
10.10.1.255
is the
broadcast address.
126
addresses would be designated.
Table 21.1 SNMP Settings
Field Description