What are the right commands for making a backup image for primary boot partition ?

Dear Hesham,

you can always use dd command  to make backup image of any partition, like the following example

dd if=/dev/sda1 of=/Path/backup.sda1.img bs=1M conv=noerror

tip: you can use gzip to compress the image

dd if=/dev/sda1 bs=1M conv=noerror| gzip -c  > /Path/backup.sda1.img

good luck