How do I set a static IP address for this router:
so that a specific MAC address always gets the same IP address.
11 Answer
How do I set a static IP address for a particular MAC address?
"Setup" > "Lan Setup" > "Network Address Server Settings (DHCP)" > "Pre-assigned DHCP IP Addresses"
Here you can assign static (fixed) IP adresses to specified MAC addresses.
You also need to enable the DHCP server to use static (fixed) fixed IP addresses.
Setup > Lan Setup
The Setup Lan Setup page allows you to configure the settings for the Local Area Network (LAN) in your home. These settings include the range of IP addresses that define the LAN itself as well as how the addresses are assigned (automatically by DHCP or manually) as new devices are added to the network.
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Network Address Server Settings (DHCP)
DHCP Server
Allows you to enable or disable the DHCP server in the residential gateway. The DHCP server is used to automatically allocate IP addresses to devices Pre-assigned DHCP IP Addresses page
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Click Pre-assigned DHCP IP Addresses in the Lan Setup page. The Pre-assigned DHCP IP Addresses page opens. This page allows you to assign a specific IP address to a PC or other device when they request an IP address using DHCP. Only addresses within the range of the gateway's DHCP address pool can be reserved with this feature.
Source Cisco Model DPC 3825 and EPC 3825 8x4 DOCSIS 3.0 Wireless Residential Gateway User Guide, p32
