1. Configuring Cisco 2650 Router By John Teissonniere Manny Jacome
Cisco IOS DHCP Server
Configuring Cisco 2650
Router
By John Teissonniere
Manny Jacome
5/2/2019

2. What Is Dynamic Host Control Protocol?
Provides configuration parameters, such as:
Client IP address and subnet mask
Default gateway
5/2/2019

3. Network Implementation
Single LAN
VLANs using a relay agent
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4. DHCP IOS Server
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5. How Does It Work DHCPDISCOVER (broadcast) UDP protocol, port 67
Destination address of
Source address
Relay agent (ip helper-address)
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6. How Does It Work
DHCPOFFER (unicast message can be from one or several DHCP servers)
Offer on port 68
Lease time
Renewal time
Domain name server
Wins server
DNS server
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7. How Does It Work DHCPREQUEST Broadcast (to all DHCP servers available)
Server identifier option field
No ip address yet
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8. How Does It Work DHCPACK(unicast) Contains network information
Client in bound state
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9. Benefits of DHCP Reduced internet access costs
Reduced client configuration tasks and costs
Centralized management
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10. Configuring the Server
Identify TFTP,FTP,RCP servers to store database
Identify assignable IP addresses
Identify DHCP options for devices:
Default router(s)
DNS server(s)
NetBIOS name server
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11. IPCONFIG / All
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12. To Configure Cisco IOS DHCP Server Feature (Steps)
Configure a DHCP database agent or
disabling DHCP conflict login
Excluded IP addresses
Configure a DHCP address pool
DHCP relay agent using IP helper-address command (performed at the switch)
5/2/2019