unable to resume after hibernation
 

I am using Debian wheezy AMD64 7.0 and at present I am unable to resume after hibernation. When I issue the command update-initiates -u I am getting the following error
failed to detect canonical device of /dev/sda2(swap partition).

please help me to resolve this issue like adding an entry to crypttab etc.,
Please explain the process in detail because I am new to Linux.

Regards,
Rupesh.

Do you mean update-initramfs?
what's the output of fdisk -l?

I have stayed away from using hibernation because it uses the SWAP partition to store the memory image. In doing this it wipes the SWAP partition formatting. Someplace in the hibernation restore the SWAP partition must be re-formatted as SWAP, before SWAP is started.
This is from memory, but I think it is explained in the kernel docs.