[CentOS] Weird /dev/dm-0

Dear All,


I got a little problem installing rhel 4u7. I have 4 x 146Gb disk on my server.
2 x 146 with raid 1 and 2 x 146 without raid. When I installing rhel
4u7 a got 3 disk /dev/sda, /dev/sdb and /dev/sdc
The problem is, after I finish installing the os, there are another
device appears in fdisk -l
/dev/sda1, /dev/sdb1, /dev/sdc1, and /dev/dm-0p1. And i can't mount
the /dev/sdb1 it said device is busy.
I can't mount /dev/dm-0p1 either.

I don't have any multipathd install in my system, but why rhel4u7
create that /dev/dm-0 device?
Really need advice from you all guys..


BestRegards,

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