NSA 325 v2 boot from GPT hard disk

[Jutzi]

I installed ARCH Linux ARM to NSA 325 v2 using the instructions here: http://archlinuxarm.org/platforms/armv5/zyxel-nsa325

I have a 3TB disk. Installation script configures the disk as an MBR disk with a limit of 2TB. Seems that GTP is not supported but hybrid MBR could work. Some information here: http://www.rodsbooks.com/gdisk/hybrid.html

There seems to be lots of options how to make the partitions and I have no idea what is required by the booting system. Have anybody done this?

[Jutzi]

I managed to make the GPT disk bootable. Gdisk with mostly default values worked fine as said here:
viewtopic.php?f=58&t=6561&p=36537&hilit=hybrid+mbr#p36536

Using gdisk I did three partitions, first two for the system (boot and rootfs) and then third partition rest of the disk. Using gdisk hybrid partition tool under r (recovery) option converted first two partitions to MBR partitions. That's it.

[moonman]

In case you don't want 3 partitions, you can get away with 2. Only partition containing the kernel needs to be in MBR. As soon as the kernel is loaded it knows about GPT partitions. There will be a new uboot with support for GPT too as WarheadsSE has most of the work done on it already.

[Jutzi]

I need three partitions. I will install LVM over the two disks.

Works fine but fdisk does not recognize the hybrid disk partitions right. I assume this does not cause problems later.
Here is how the GTP partitions actually are:

/dev/sdb1 2048 34815 32768 16M Linux filesystem
/dev/sdb2 34816 41977855 41943040 20G Linux filesystem
/dev/sdb3 41977856 5860533134 5818555279 2.7T Linux filesystem

and this is how fdisk reports:

Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 34815 32768 16M 83 Linux
/dev/sda2 34816 41977855 41943040 20G 83 Linux
/dev/sda3 1 2047 2047 1023.5K ee GPT

Partition 4 does not start on physical sector boundary.

I use the first two /dev/sdb partitions as backup for the two system partitions, just in case.

[moonman]

I don't see anything wrong with it.