# Configuration for pmbr?



## hermes (Mar 27, 2010)

Okay, guys. Iâ€™ve set up an encrypted (keyfile + passphrase) root partition on ZFS, using GPT as partitioner:


```
=>       34  625142381  ad4  GPT  (298G)
         34        128    1  freebsd-boot  (64K)
        162    1024000    2  freebsd-ufs  (500M)
    1024162    8388608    3  freebsd-swap  (4.0G)
    9412770  615729645    4  freebsd-zfs  (294G)
```
The first two partitions are intended as Â»emergencyÂ« boot partitions. Obviously, I donâ€™t want the keyfile to reside on ad4p2, but instead boot off an USB key. Now, the system boots fine off ad4, however it will not boot off a USB key, neither with MBR nor GPT partitioning scheme (I know the mainboard is capable of booting off USB, and the stick is bootable using my laptop, but the combination mainboard/USB key with GPT/BSD partitioning will not work, I donâ€™t know why. :/ The mainboard is an MSI K9A Platinum btw.)
The proposed solution is the following: Let the mainboard load the MBR (pmbr obviously since itâ€™s a GPT partition) off ad4, but tell the FreeBSD bootloader on ad4 to use da0 (the USB key) to load /boot/kernel/kernel from. This would not be a problem at all with the traditional boot0 loader, using boot.config(5), but how do you do that with pmbr? (The USB key is recognised as disk2 by the BIOS). I couldnâ€™t find any good documentation on the web.


----------



## hermes (Mar 27, 2010)

Okay, I was stupid. It seems /boot.config is indeed respected, I just placed it on the USB key instead of the hard drive boot partition. >.<


----------

