Cisco Catalyst 4500 Series, Software Configuration Manual

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Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 59 Configuring the Cisco IOS DHCP Server
Information About Cisco IOS DHCP Server
Table 59-1 Static Mapping Text File Field Descriptions
DHCP Server Operation
By default, the DHCP server pings a pool address twice before assigning a particular address to a
requesting client. If the ping is unanswered, the DHCP server assumes (with a high probability) that the
address is not in use and assigns the address to the requesting client.
By default, the DHCP server waits for 2 seconds before timing out a ping packet.
Field Description
*time* Specifies the time the file was created. This field
allows DHCP to differentiate between the new
and old database versions when multiple agents
are configured. The valid format of the time is mm
dd yyyy hh:mm AM/PM.
*version* 2 Specifies the database version number.
IP address Specifies the static IP address. If the subnet mask
is not specified, a mask is automatically assigned
depending on the IP address. The IP address and
the mask is separated by a space.
Type Specifies the hardware type. For example, type
“1” indicates Ethernet. The type “id” indicates
that the field is a DHCP client identifier. Legal
values can be found online at
http:/?/?www.iana.org/?assignments/?arp-parame
ters in the “Number Hardware Type” list.
Hardware address Specifies the hardware address.
When the type is numeric, the type refers to the
hardware media. Legal values can be found online
at
http://www.iana.org/?assignments/?arp-paramete
rs
in the “Number Hardware Type” list.
When the type is “id,” the type refers to a match
on the client identifier.
For more information about the client identifier,
see RFC 2132, DHCP Options and BOOTP
Vendor Extensions, section 9.14, located at
http://www.ietf.org/rfc/rfc2132.txt , or the
client-identifier command.
If you are unsure about the client identifier to
match with the hardware type, use the
debug
dhcp detail command to display the client
identifier being sent to the DHCP server from the
client.