GRUB Installation Issue with 2 TB HDD

Few days ago i need across to install  a box with 2 x 2 TB HDD WD  Caviar Green with  Debian Squeeze with RAID 1. So I started the installation.

Even now I have noticed some strange, when partitioning first hd it don't ask me to set primary partition and bootable flag was not exchangeable

Apart from this was going well until the GRUB installation. It failed with the error message below!

Sep 22 01:34:43 grub-installer: grub-setup: warn: This GPT partition label has no BIOS Boot Partition; embedding won’t be possible!
Sep 22 01:34:43 grub-installer: grub-setup: error: Embedding is not possible, but this is required when the root device is on a RAID array or LVM volume

I started googlin for two days, with numeros forum suggestion with technical details about WD caviar green 4KB sector setup on linux and relative bugs, GPT configuration suggestion... all these attemps failed! :(   

Today I decided to try another way... and this time successfully :)

Problems could be solved adding a small partition (200MB) BIOS Boot Partition which was missing on both sda devices.

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