ADC CUDA 3 User Manual

Page 267

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Cuda 12000 IP Access Switch CLI-based Administration Guide

About DHCP Authority

265

When the DHCP relay agent sees this acknowledgement, it then checks
to verify whether the IP address falls within a DHCP authority range
configured on the interface, and one of the following actions occur:

If the address does fall within a preconfigured DHCP authority range and
DHCP Authority is enabled for that interface, an ARP entry is added to the
ARP cache for that interface and tagged as being assigned through DHCP.
This tag is shown as type “Other” when viewing the ARP cache for that
interface and ensures that specific IP address only maps to that specific
MAC address.

or

If there is no DHCP Authority range, the entry is simply added to the ARP
cache and labelled as type “Dynamic” when the ARP mapping is learned.

This feature is termed DHCP authority because those tagged as being
assigned through DHCP take precedence over dynamically assigned
(non-DHCP tagged) ARP entries. In the ARP cache entries that follow, those
labelled as other are protected by DHCP authority, those labelled as dynamic
are not:

cli:172.16.19.10:interface:cable:csi(1/1/1)# show arp

row count: 4

IP Address MAC Address Type

---------------- ------------------ ----------

192.168.19.51 00:10:95:04:0a:c4 dynamic

192.168.19.52 00:10:95:04:0a:b7 dynamic

192.168.19.55 00:10:95:01:ef:d8 other

192.168.19.56 00:a0:73:69:39:65 other

cli:172.16.19.10:interface:cable:csi(1/1/1)#

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