[CentOS] permanently add md device

Hi All

Currently i'm setting up a 5.4 server and try to create a 3rd raid device, when i run:
$mdadm  --create /dev/md2 -v  --raid-devices=15 --chunk=32 --level=raid6 /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg /dev/sdh /dev/sdi /dev/sdj /dev/sdk /dev/sdl /dev/sdm /dev/sdn /dev/sdo /dev/sdp /dev/sdq

the device file "md2" is created and the raid is being configured. but somehow /dev/md2 is flushed when i reboot the system , same story if i create the file by mknod or MAKEDEV.
does anyone know a way to solve this issue and permanently add md2 to devices?

Thanks,

Wessel