CentOS 4 installer sees /dev/sda, but after boot it's /dev/sdb

[Jeff Larsen]

PE 2950, SAS onboard RAID, 2 RAID 1 arrays

bash-3.00# ls -l /dev/sd*
brw-rw----  1 root disk 8,  0 Apr 29 05:15 /dev/sda
brw-rw----  1 root disk 8, 16 Apr 29 05:15 /dev/sdb
brw-rw----  1 root disk 8, 17 Apr 29 05:15 /dev/sdb1
brw-rw----  1 root disk 8, 18 Apr 29 05:15 /dev/sdb2
brw-rw----  1 root disk 8, 19 Apr 29 05:15 /dev/sdb3
brw-rw----  1 root disk 8, 32 Apr 29 05:15 /dev/sdc


bash-3.00# fdisk /dev/sda

Unable to open /dev/sda

What's the deal?

-- 
Jeff