Hi Afonso,
MSA 1050 does not support linear storage. Hence the steps to expand a vdisk does not apply here.
In virtual storage, you cannot expand existing disk groups. To add more disks to the pool you could create a new disk group and assign it to the same pool which owns the existing disk groups.
It is recommended to use same RAID type as your existing disk group.
RAID 1. Requires 2 disks.
RAID 5. Requires 3-16 disks.
RAID 6. Requires 4-16 disks.
RAID 10. Requires 4-16 disks, with a minimum of two RAID-1 subgroups, each having two disks.
Regards,
Rakesh S