[CentOS] How to test RAID-5

Hi all,
1. Is RAID-5 fault tolerant?
2. I make a RAID-5 array with 3 disk. The /boot is on RAID-1 partition, the 
rest are raided 5. When I simulate disk failure by unplugging sda and 
restarting Centos. Grub fails in stage 1.5. What is the correct way of 
simulating harddisk failure in RAID-5? If I unplug the other drives, it 
manages to boot ok.
Thank you.
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Fajar Priyanto | Reg'd Linux User #327841 | Linux tutorial 
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