This command enables a router to receive messages from Cisco Unified
IP phones through the specified IP address and port.
The Cisco Unified CME router cannot communicate with Cisco Unified
CME phones if the IP address of the port to which they are attached is not
configured. In Cisco Unified CME 8.0 and later versions, the Cisco Unified CME
router can receive messages from IPv6-enabled or IPv4-enabled IP phones or from
phones in dual-stack (both IPv6 and IPv4) mode.
- In Cisco Unified CME 8.0 and later versions: If the IP phones
connected to Cisco Unified CME were configured for dual-stack mode by using
dual-stack keyword with the
mode command, configure this command with the
- In Cisco Unified CME 8.0 and later versions: If the IP phones to
be connected to the port to be configured are IPv4-enabled only
or IPv6-enabled only, configure this command with the
corresponding IPv4 or IPv6 address.
For IPv6: Do not configure the
port keyword argument combination in this
command to change the value from the default (2000). If you change the port
number, IPv6 CEF packet switching engine will not be able to handle the IPv6
SCCP phones and various packet handling problems may occur when more than a
dozen (approximately) calls in IPv6 are going on.
keyword to instruct the router to reject IP phone registration
attempts if the IP server address used by the phone does not match the source
Prior to Cisco IOS Telephony Services (Cisco ITS) V2.1, this command
helped the router to autogenerate the SEPDEFAULT.cnf file, which was stored in
the flash memory of the router. The SEPDEFAULT.cnf file contains the IP address
of one of the Ethernet ports of the router to which the phone should register.
In ITS V2.1 and in Cisco CME 3.0 and later versions, the
configuration files were moved to system:/its/. The file named
Flash:SEPDEFAULT.cnf that was used with previous Cisco ITS versions is
obsolete, but is retained as system:/its/SEPDEFAULT.cnf to support upgrades
from older phone firmware.
For systems using Cisco ITS V2.1 or later versions, the IP phones
receive their initial configuration information and phone firmware from the
TFTP server associated with the router. In most cases, the phones obtain the IP
address of their TFTP server using the
command and Dynamic Host Configuration Protocol (DHCP). For
Cisco ITS or Cisco CME operation, the TFTP server address obtained by the Cisco
Unified IP phones should point to the router IP address. The Cisco IP phones
attempt to transfer a configuration file called XmlDefault.cnf.xml. This file
is automatically generated by the router through the
source-address command and is placed in router
memory. The XmlDefault.cnf.xml file contains the IP address that the phones use
to register for service, using the SCCP. This IP address should correspond to a
valid Cisco CME router IP address (and may be the same as the router TFTP
Similarly, when an analog telephone adapter (ATA) such as the ATA-186
is attached to the Cisco Unified CME router, the ATA receives very basic
configuration information and firmware from the TFTP server XmlDefault.cnf.xml
file. The XmlDefault.cnf.xml file is automatically generated by the Cisco
Unified CME router with the
source-address command and is placed in the
router’s flash memory.
By specifying a second Cisco Unified CME router in the
source-address command, you improve the failover
time for phones.
The following example sets the IP source address and port:
Router(config-telephony)# ip source-address 10.6.21.4 port 2000 strict-match
The following example establishes the router at 10.5.2.78 as a
Router(config-telephony)# ip source-address 10.0.0.1 port 2000 secondary 10.5.2.78
The following example shows how to configure this command with an
IPv6 address. Do not change the port number from the default value (2000) when
you configure an IPv6 address.
Router(config-telephony)#protocol mode ipv6
Rounter(config-telephony)ip source-address 2001:10:10:10::3
The following example shows how to configure an IP address for
dual-stack mode. When the IP phones are configured for dual-stack mode, the IP
address of the router port to which the IP phones are connected must be an IPv6
address. For dual-stack mode, the address of the secondary router must be an
Router(config-telephony)# protocol mode dual-stack
Router(config-telephony)# ip source address
2001:10:10:10::3 secondary 10.5.2.78