I tried to set up the following partitioning scheme: part /boot --size=512 --ondisk=sda --asprimary part / --size=512 --ondisk=sdb --asprimary part /usr --size=4096 --ondisk=sda part /var --size=4096 --ondisk=sdb part /tmp --size=8192 --ondisk=sda part /cache --size=4096 --ondisk=sdb part swap --size=4096 --ondisk=sdb part raid.00 --size=1 --ondisk=sda --grow part raid.01 --size=1 --ondisk=sdb --grow raid pv.00 --level=0 --device=md0 raid.00 raid.01 The caveat is that sda and sdb are each 1.1TB in size. Anaconda fails with the somewhat cryptic message: "Error informing the kernel about modifications to /dev/sda2 - Invalid argument. This means that Linux won't know about any modifications made to /dev/sda2 until you reboot - so you shouldn't mount it or use it in any way before rebooting." Removing --grow and setting --size to something "reasonable" like 1000000 makes things work properly. I'm not sure what limit is coming into play here. It doesn't seem to be the kernel's 2TB limit because the RAID array hasn't been set up. Running sfdisk -l on VT2 doesn't show any changes to the partition table at all.
Mike can you test this on any of our available hardware?
We set limits to 1TB now. Anything else is a crap shoot depending on what hardware is being used and a few other factors.