Transferred the system, installed grub - how to boot further?

Question

linux

Good afternoon, hackers. Help with problem solving.
I had a 640GB hard drive in my laptop, with a system on /dev/sda1 with a size of 241Gig.
I decided to replace it with an Intel SSD 240Gb.
One gig was not enough, I didn’t want to bother with transferring files for a long time, so with the help of gparted I reduced /dev/sda1 to 239. I quickly transferred it to /dev/sdb1 with the help of dd , after creating it. I put grub on /dev/sdb , but at startup I see something like "BootDevice not found, Install Operation System". From the old screw the system starts as before. Thanks in advance.

Answer 1

Thanks everyone, problem solved. The boot flag for the partition was missing.

Answer 2

For example, using LiveCD

Answer 3

How is the system drive specified in the kernel settings? root=/dev/sda1 or UUID? The disk has changed, its UUID has also changed (and if anything, the Label does not change, it is already written inside the disk)