Cisco Cisco IOS Software Release 12.2(2)XA

Use the timing hookflash-out command to specify the duration of hookflash indications that the 
gateway generates on an FXO interface. The no form of this command resets hookflash to the default 
value.

timing hookflash-out duration

A duration can be between 50 and 500 milliseconds.

Default value is 300ms.

Privileged EXEC 

This command specifies a duration of hookflash indications. Hookflash indications may be generated 
when relayed from an IP network during a VoIP call. Depending on the vendor and country, PBXs and 
switches vary in their definition of the duration of a hookflash. This command allows you to adjust the 
hookflash duration appropriately for your network.

To implement timing for the hookflash with a duration of 200ms, enter the following command syntax 
after you have configured voice-port 1/0/0:

Router# configure terminal

Router(config)# voice-port 1/0/0

Router(config-voiceport)# timing hookflash-out 200

12.0(5)T

This command was first introduced.

12.1(5)XM2

This command was introduced for the Cisco AS5350 and CiscoAS5400.

12.2(4)T

Support for the Cisco AS5300, Cisco AS5350, and Cisco AS5400 is not 
included in this release.

12.2(2)XB1

This command was implemented on the Cisco AS5850 platform.

Switch to the voice-port configuration mode form the global 
configuration mode.