Dynamic Host Configuration Protocol; Configuring Dhcp Relay Service - Edge-Core ES4612 Management Manual

CLI - This example displays all the resource records learned from the designated
name servers.
Console#show dns cache
NO FLAG TYPE
0 4 CNAME
1 4 CNAME
2 4 CNAME
3 4 CNAME
4 4 CNAME
5 4 ALIAS
6 4 CNAME
7 4 ALIAS
8 4 CNAME
9 4 ALIAS
10 4 CNAME
Console#

Dynamic Host Configuration Protocol

Dynamic Host Configuration Protocol (DHCP) can dynamically allocate an
IP address and other configuration information to network clients when they boot up.
If a subnet does not already include a BOOTP or DHCP server, you can relay DHCP
client requests to a DHCP server on another subnet, or configure the DHCP server
on this switch to support that subnet.
When configuring the DHCP server on this switch, you can configure an address
pool for each unique IP interface, or manually assign a static IP address to clients
based on their hardware address or client identifier. The DHCP server can provide
the host's IP address, domain name, gateway router and DNS server, information
about the host's boot image including the TFTP server to access for download and
the name of the boot file, or boot information for NetBIOS Windows Internet Naming
Service (WINS).

Configuring DHCP Relay Service

This switch supports DHCP relay
service for attached host devices.
If DHCP relay is enabled, and this
switch sees a DHCP request
broadcast, it inserts its own IP
address into the request so that
the DHCP server will know the
subnet where the client is located.
Then, the switch forwards the
packet to the DHCP server. When
the server receives the DHCP request, it allocates a free IP address for the DHCP
client from its defined scope for the DHCP client's subnet, and sends a DHCP
response back to the DHCP relay agent (i.e., this switch). This switch then
broadcasts the DHCP response received from the server to the client.
Dynamic Host Configuration Protocol
IP TTL
207.46.134.222 51
207.46.134.190 51
207.46.134.155 51
207.46.249.222 51
207.46.249.27 51
POINTER TO:4 51
207.46.68.27 71964
POINTER TO:6 71964
65.54.131.192 605
POINTER TO:8 605
165.193.72.190 87
DOMAIN
www.microsoft.akadns.net
www.microsoft.akadns.net
www.microsoft.akadns.net
www.microsoft.akadns.net
www.microsoft.akadns.net
www.microsoft.com
msn.com.tw
www.msn.com.tw
passportimages.com
www.passportimages.com
global.msads.net
Provides IP address
compatible with switch
segment to which client
is attached
3
4-147
DHCP
Server
3-169