How to recover undelete deleted file dhcpd.leases file?

I made a back up of DHCP but when i unstinalled it the back up was removed. How can i recover dhcpd.leases Example /var/lib/dhcpd/dhcpd.leases its on /dev/mapper/vg_server-lv_root i did do a locate dhcpd.leases no results were found OS Centos 6 Thank you in advance. I tried testdisk on the logical drive but it would not work with /dev/mapper/vg_server-lv_root