I must say, it was difficult to name this question.
Basically, I need to properly reinstall the bootloader on my system, because I already have the working system disks for my OSes.
The long story is this: I had the large slow HDD with Windows7 & Debian Wheezy dual-boot on it, perfectly bootable. Then, I ordered the SSD drive and prepared my system partitions to fit onto the much smaller SSD. I wanted the following schema:
128 GB Windows 24 GB / on Debian 86 GB /home on Debian
Strange size for
/home because there's no such thing as true 256GB disk drive.
So, I've prepared such a partitions on my initial HDD and installed the new SSD and then I loaded the GParted live USB (can't remember now how it was really named), and then just copypasted the partitions from HDD to SSD.
So, now I have the following partitions across the physical disks:
SSD 128 GB copy of original Windows partition 24 GB copy of presumably Debian / 86 GB copy of presumably Debian /home HDD 128 GB Windows 24 GB / on Debian 86 GB /home on Debian ... several other partitions with non-system data ...
And the behavior of the system right after the Ctrl+C, Ctrl+V in GParted was as follows: no GRUB, system boots right into the Windows on HDD.
In BIOS settings are to boot from SSD first.
I managed to create the Debian Testing installation USB and loaded it into the rescue mode, found that it identified my SSD as /dev/sda and installed the GRUB to the /dev/sda. Now my system loads the GRUB which lists both Windows and Debian. From HDD. So, I am now back into initial position.
Please, how I should set up the GRUB so it'll load the OSes correctly from SSD?
Should I fire up my Debian, fiddle with the GRUB's config and reinstall it again to the same place (at SSD)?