I am sort of newbie to linux, using hit & trial method to learn something new

Anyways I have just acquired dual drive (250GB each) Pre-Configured dedicated server which was installed using the install link provided in panel.

I have installed webmin / virtualmin to easyfy things

I want to use the 2 drives for RAID1

Below is the output of few commands I know

[root]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/vg-root 225G 25G 189G 12% /
tmpfs 1.9G 0 1.9G 0% /dev/shm
/dev/sda1 243M 68M 162M 30% /boot
/dev/mapper/vg-tmp 976M 4.1M 921M 1% /tmp
[root]# mount
/dev/mapper/vg-root on / type ext4 (rw,noatime,grpquota,discard,usrquota)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw)
/dev/sda1 on /boot type ext2 (rw)
/dev/mapper/vg-tmp on /tmp type ext4 (rw,noatime,discard)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)