[ubuntu] how to change the disk to boot from ?

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http://ubuntuforums.org – Hi, After have been released new grub* ubuntu packages couple of days ago and have been properly installed ... my booting disk sequence has been changed. --- sda DATA disk sdb booting disk , grub sdc DATA disk sdd booting disk , grub --- before installation it was ok and booting has been done from sdb which is correct. after grub* packages have been installed - booting (grub menu) is taken from sdd disk instead of from sdb. Is there any way how to force it to boot from sdb again ? (Both disks sdb and sdd are properly booting if I choose one of them to boot from BIOS) thank (Hardware)