Hi Chandrasen,
Try this setting :)
RNA Reversion Timeout
Enter a time, in seconds, after which Cisco CallManager will distribute a call to the next available or idle member of this line group or to the next line group if the call is not answered and if the first hunt option, Try next member; then, try next group in Hunt List, is chosen. The RNA Reversion Timeout applies at the line-group level to all members.
Under "Line Group Configuration", you can find (and change) the "RNA Reversion Timeout" (which is by default set to 10 seconds)
From this doc;
http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_administration_guide_chapter09186a00803edabe.html#wp107892
If the call goes unanswered then a Forward should be applied at the "Hunt Pilot" Level that routes the caller to Unity;
Hunt Forward Settings
Forward Hunt No Answer - When the call that is distributed through the hunt list is not answered in a specific time, this field specifies how to forward the call.
Destination This setting indicates the directory number to which calls are forwarded.
Forward Hunt Busy - When the call that is distributed through the hunt list is busy in a specific time, this field specifies how to forward the call.
Destination This setting indicates the directory number to which calls are forwarded.
Maximum Hunt Timer - Enter a value (in seconds) that specifies the maximum time for hunting.(Used in conjunction with Forward Hunt Busy)
Hope this helps!
Rob
