Specifications

2-8
Cisco IOS Telephony Service, Version 2.02
Chapter 2 Required Configuration Tasks
How to Configure Cisco IOS Telephony Service
Configuring DHCP Relay
This process configures DHCP Relay on the LAN interface where the Cisco IP phones are connected and
enables the Cisco IOS DHCP Server feature. For further details about DHCP configuration, refer to the
Cisco IOS DHCP Server document.
Note By default, the Cisco IOS DHCP Server feature is enabled on your router. If the feature is disabled,
enable the Cisco IOS DHCP Server feature on your router.
SUMMARY STEPS
1. service dhcp
2. interface type number
3. ip helper-address ip-address
DETAILED STEPS
:
Step 5
Router(config-dhcp)# option 150 ip ip-address
Specifies the TFTP server IP address from which
the Cisco IP phone downloads the image
configuration file, SEPDEFAULT.cnf. This is your
Cisco IOS Telephony Service router IP address.
Step 6
Router(config-dhcp)# default-router ip-address
Specifies the IP address of the default router. The
Cisco IP phones are directly connected to this
router. This router is either a Cisco IOS Telephony
Service router or any Cisco router attached to the
Cisco IOS Telephony Service router.
Note As long as the Cisco IP phones have
connection to the Cisco IOS Telephony
Service router, the Cisco IP phones are
able to get the required network details.
Command Purpose
Command Purpose
Step 1
Router(config)# service dhcp
Enables the Cisco IOS DHCP Server feature on
the router.
Step 2
Router(config)# interface type number
Enters interface configuration mode for the
specified interface.
Step 3
Router(config-if)# ip helper-address ip-address
Specifies the helper address for any unrecognized
broadcast for TFTP server and Domain Name
System (DNS) server requests. For each server, a
separate ip helper-address command is required
if the servers are on different hosts. You can also
configure multiple TFTP server targets by using
the ip helper-address commands for multiple
servers.