Question: My current situation is:

* One hard disk
* Dual boot Ubuntu 11.04 and Windows 7. Partitions:
	+ 100MB Windows System thingy
	+ 144GB Main Windows
	+ 160GB Ubuntu
	+ 4GB Swap
	+ 12GB System Restore stuff

Now I want to install an 80GB SSD and move Ubuntu to it. AFAIK I need to:

* Shrink the 160GB Ubuntu partition to 80GB
* Copy it over to the SSD
* Change `fstab` to mount the SSD as `/`

How do I do the second? And what do I need to do about Grub?

Answer: 
Here is as good (for 2018) as easy how-to from 2013: <http://www.sesser.eu/howtos/hdd2ssd.php> by Markus Sesser.
But you should read 1st comment here about `--exclude "sys"` - thanks to @em2er !

It describes migration without booting from live CD. It also respects system dirs and uses **rsync**, **noatime**, **nodiratime**. Just do not forget to omit **discard** option - it is implemented via cron since Ubuntu 14.04.

Short plan from article:

1. partition and mount the SSD.
I recommend single ext4 on gpt
2. cleanup source HDD
3. sync data (**rsync**)
4. tune **fstab**. Also if you will keep HDD in system then I recommend move /home onto SSD while keep user data (~/Video, ~/Audio, etc.) on HDD
5. install **grub**
Considering your HDD is /dev/sda and SSD is /dev/sdb and partitions are properly sized, you may use simple cp:

```
cp /dev/sdaX /dev/sdbY

```

Where X and Y are corresponding partition numbers.

However this method will copy 80GB of data and all sectors on your SSD will be marked as "occupied" initially.