Have two partitions in RAID1

Question

The answers are unclear wherever I look. I have two 2TB drives for a RAID1 and I want to mirror them while having two partitions on the drives. One partition will be 100GB and contain programs, the other partition will be 1.8TB and contain personal files.

Some may ask why? The answer is that my programs are currently on another older drive and I want to save time and pain uninstalling and re-installing critical programs while merely copying them to the new drives via Shadowcopy.

When I create the RAID1, will both partitions be mirrored? Is this possible?

I am sorry if I am being confusing or unclear.

Solution

RAID can be used to mirror whole disks or just partitions, though support varies depending on which RAID method you use.

Hardware RAID cards tend to mirror only whole disks. After creating a mirror of a whole disk you can create multiple partitions on that new virtual disk.

Windows software RAID seem to mirror partitions. This does not prevent you from creating two mirrors, one sided 100GB and one sized 1.8TB. Just realise that this might not automatically clone the boot sector or non-obvious partitions, resulting in problems [such as this one].

Linux software RAID (MDx) can do both volumes and whole disks (The result of handling both whole disks and partitions as files). You can even use md to create a new RAID array without loosing old data if you do it like this.

For more detailed information we would need to know which OS you are using and/or which RAID method. Software RAID via the OS, fake RAID (Intel), HW RAID (and which model).

Could you add this information to your post? And comment on this? (The latter so I get a ping and I can update this 'comment' posted as an answer (due to lack of proper markup and length restrictions in comments). Alternatively drop in on our generic chat room. It is not the place for live support but if I am active in it I can answer in a lot more detail.

Comments

[user1984103]

RAID-1 will mirror the entire disks, including the partition table and partitions.

[mateikav]

which means that both my partitions will be mirrored and intact?

[user1984103]

That depends largely upon what method you're using to mirror them. Some RAID setups will format the disks before creating a RAID out of them, others can convert a non-RAID disk into a RAID disk with no loss of data. Either way, I wouldn't use a RAID 1 setup for the purpose of copying data. Use a disk imaging tool.

[Jason McD]

I don't think you want to do RAID-1 but rather some auto mirroring software. I think you would get into more headaches trying to setup a software raid like that.

[mateikav]

That sounds like a good idea Jason McD...I'm going to try MirrorFolder

[Jason McD]

Dang it! I could have gotten a checkmark =)

[Sun]

Post your comment as an answer and delete the comment. Let the OP mark as an answer. :)