[CentOS] Booting Software RAID

[Matt]

> I installed Centos 6.x 64 bit with the minimal ISO and used two disks
> in RAID 1 array.
>
> Filesystem      Size  Used Avail Use% Mounted on
> /dev/md2         97G  918M   91G   1% /
> tmpfs            16G     0   16G   0% /dev/shm
> /dev/md1        485M   54M  407M  12% /boot
> /dev/md3        3.4T  198M  3.2T   1% /vz
>
> Personalities : [raid1]
> md1 : active raid1 sda1[0] sdb1[1]
>       511936 blocks super 1.0 [2/2] [UU]
> md3 : active raid1 sda4[0] sdb4[1]
>       3672901440 blocks super 1.1 [2/2] [UU]
>       bitmap: 0/28 pages [0KB], 65536KB chunk
> md2 : active raid1 sdb3[1] sda3[0]
>       102334336 blocks super 1.1 [2/2] [UU]
>       bitmap: 0/1 pages [0KB], 65536KB chunk
> md0 : active raid1 sdb2[1] sda2[0]
>       131006336 blocks super 1.1 [2/2] [UU]
>
> My question is if sda one fails will it still boot on sdb?  Did the
> install process write the boot sector on both disks or just sda?  How
> do I check and if its not on sdb how do I copy it there?

Based on input from everyone here I am thinking of an alternate setup.
 Single small inexpensive 64GB SSD used as /boot, / and swap.  Putting
/vz on software RAID1 array on the two 4TB drives.  I can likely just
zip tie the SSD in the 1u case somewhere since I have no more drive
bays.  Does this seem like a better layout?