14 JanBoot from either disk of a RAID1 Mirror

I always forget this series of commands and have trouble locating them. After setting up a RAID1 mirror set, I want to be sure I can boot off of either drive in case of a drive failure. Assume two SATA drives, /dev/sda and /dev/sdb. The first will be set up during the OS install. To be sure the second drive also has the right info in its MBR, do this as root:

grub
grub>device (hd0) /dev/sdb
grub>root (hd0,0)
grub>setup (hd0)
grub>quit

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