The NAS I've worked with usually were set like this:
First partition is for the linux file system and is mirrored to all the drives in the NAS, in the place where were SWAP partition it was also mirrored. The space where the user data is stored - LVM as type of array.
For recovery I used "systemrescuecd" since it have build in LVM support. To be sure about the type of the raid you must check the /etc/fstab. It could look like this:
Code:
/dev/md0 / ext3 defaults 1 1
none /proc proc defaults 0 0
none /sys sysfs defaults 0 0
/dev/sda2 swap swap defaults 0 0
Also if you check the drives especially the place where 461.83 GB partition start, probably you will find something alike to :
Code:
<DynamicDiskSegment guid="13e6d7f8-8660-6d0b-e886-0000476b7c82" firstSector="16128" lastSector="22271" owner="DIMASTYLE-NAS" dataset="1198226562" seqNo="0" isLastSegment="true" sectorSize="512" type="Umap" lunType="0" timestamp="1198226562" umapTimestamp="0" deviceName="NASDisk-00002" fileSystem="XFS"/>
<DynamicDiskSegment guid="13e6d7f8-8660-6d0b-e886-0000476b7c82" firstSector="22272" lastSector="3417620223" owner="DIMASTYLE-NAS" dataset="1198226562" seqNo="1" isLastSegment="true" sectorSize="512" type="NAS" lunType="0" timestamp="1198226562" umapTimestamp="0" deviceName="NASDisk-00002"/>
Some of those things will be very useful to you, to rebuild the LVM.
P.S. Ask Google, there are several interesting places where the LVM is described, as and the way it can be recovered (commands and etc.)
P.S.2 You may be a lucky one because LVM (as I checked it for one NAS) use successive way to store the data. I.e. start to write form the first drive (XFS partition) when it is full, go to second one and etc. So you may use even by signature.
Hope I was in help with this.