Expandable filesystem with more disk

[Markus Örebrand]

I need a possibility to expand a filesystem by adding more disk. I am
sensing that a certain GEOM setup would do the job.

The ideal conditions would be:
- The filesystem is created on a GEOM. 
- Initially, the GEOM has only one consumer.
- A consumer is a FreeBSD partition (created with bsdlabel(8))
- The size of the GEOM is expandable by adding more consumers.
- The filesystem is expandable by using growfs(8).


Are these conditions realistic? What is the procedure to a) do basic
setup, b) expand the filesystem?

Would this be secure (i.e. is there a risk of data corruption or -loss)?
I am fairly confident that the hardware should pose no security risk
(hardware RAID5, UPS on disks and server).

I am thankful for all advice,

Markus Örebrand, Systems administrator @ Operax