Peregrine Systems DPND-523-EN12, Setup Manual

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Set DHCP lease time | 25
Setup Guide
Set DHCP lease time
If you use DHCP (Dynamic Host Configuration Protocol) in your network, set the
IP address lease time to at least 7 days and turn on SNMP management on the
DHCP servers.
About community strings
A community string is like a password. A device uses a community string to
protect its SNMP MIB—and it’s the data from the SNMP MIB that Network
Discovery relies on. Network Discovery must know at least one of a device’s
passwords to collect data from that device. If you do not give Network Discovery
a device’s community string, Network Discovery will behave as though the
device does not have SNMP management turned on. Network Discovery will
appear to work, but you’ll eventually notice that it is working poorly. Once
Network Discovery is up and running, the Exceptions reports can advise you of
problems.
Note: Community strings are case-sensitive. “Public” and “public” are two
different strings.
Directed community strings
Directed community strings give devices another layer of protection: a list of IP
addresses of approved devices. When Network Discovery tries to get
information from a device with a directed community string, the device asks not
only “What’s the password?” but also “Are you on the list?”
Give the Peregrine appliance IP address to all devices
using directed community strings
When directed community strings are used, it is not enough to give Network
Discovery access to the device. You must also configure the device to recognize
the Peregrine appliance. You must put it on the list of approved devices.