Cannot create /dev/md1 using mdadm after /dev/md0 is created
I am using Red Hat RHEL5.2, I am trying to set up software RAID. I use the "mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/sda8 /dev/sda9" command to create md0 out of two partitions sda8 and sda9 and is successful.
I further use fdisk to create sda10, sda11 and sda12, and try to create another raid set md1 using ""mdadm --create /dev/md1 --level=5 --raid-devices=3 /dev/sda10 /dev/sda11 dev/sda12" but this time I got the following error:
mdadm: error opening /dev/md1: No such file or directory.
I try to find the answer from the Internet, but I cannot find anything concrete. There are suggestions that this is a bug of Red Hat and some suggested that the /dev/md1 should be created first, but without giving further instruction on how to do this.