# "Manual root fs specification" error on boot, then crashes



## halfer (Apr 1, 2010)

Hi all. I am a long-time FreeNAS user, brand new FreeBSD user, and am looking to upgrade. FreeNAS is fantastic for what it does, but I want to install Huawei 3G modem support and other items that won't work (easily) within the limitations of m0n0wall. Since I think ZFS is great, I intend to plump for FreeBSD or OpenSolaris. (I've got further with the latter, but it doesn't appear to support ZFS on encrypted partitions, and I am just a beginner, and not willing to spend weeks configuring it. However such a configuration works very reliably on FreeNAS/FreeBSD via GELI, so I suspect I may have more luck in this direction. That all said, if there is an easy way to set up encrypted disks with ZFS on top in OpenSolaris, I am all ears, and do not have a preference between the two as yet).

I have burnt the 8.0 CD ISO to a DVDRW and booted it up via an external USB CD drive. I installed to a 4GB Kingston DataTraveller USB stick. This took several attempts, since I would often get "no space left on device" errors - the installer presumably didn't set the partition sizes appropriately.

To tackle the above, in the "FreeBSD Disklabel Editor" I also chose to (W)rite the partitions to disk immediately, against the advice of the UI, since the installer forgets the mount points otherwise. This enabled me to get to the Congratulations page without any space errors. I also chose the Minimal packages option.

My usb stick is partitioned in this way:


```
/	 281M
swap	 631M
/var	 217M
/tmp	 166M
/usr	2524M
```

My hardware is thus: 64 bit Intel Atom 330 (2Ã—1.6GHz) Dual Core; Memory 2Gb DDR2 533/667MHz; Motherboard Intel D945GCLF2. I am using a wireless USB keyboard as that's all I have, and it worked well during installation.

All boot options 1, 2, 3 and 4 result in an error, "Manual root filesystem specification". The machine then freezes, from which a Ctrl-Alt-Delete does nothing and the box needs to be reset. It also prints two lines beforehand, thus:


```
vfs.root.mountfrom=
vfs.root.mountfrom.options=
```

I wonder if they are meant to be completed?

So... can anyone assist me?


Unfortunately, I don't have another FreeBSD system to use or boot from
If it's a really bad idea to use a (4Gb) memory stick, do say, but some searching indicates that other people have managed it. It works nicely with FreeNAS too, inside a 1Gb stick
I am not au fait with the FreeBSD command line, but I am a fairly competent Linux/Ubuntu user
I am a technical user but have no time to learn FreeBSD or OpenSolaris in any detail - hence plumping for FreeNAS originally 
I've read the USB install FAQ and it doesn't seem to cover this eventuality
So, if a kind soul could give me some advice, that would be much appreciated!


----------



## halfer (Apr 1, 2010)

Addendum: I read somewhere that this could be due to the root FS having its name changed. When first booting the USB stick, I turned off my external CD drive, so that the USB stick was read in preference. However in case doing this changes the names of the filing systems, I kept the drive turned on, and booted from the USB stick via a BIOS menu. This made no difference, however.


----------



## phoenix (Apr 1, 2010)

Keep things simple:  for a 4 GB USB stick, create 1 slice (use Auto in the fdisk screen) and 2 partitions (root and swap).  Create the swap partition first to set the size (512 MB should be good for a 2 GB RAM system).  Then use the rest of the space for /.  sysinstall will put those in the correct location in the slice, and set the partition names correctly (b for swap and a for /).

Be sure that your BIOS is configured to support USB Mass Storage devices, that the BIOS detects your USB stick as a harddrive, and that it is configured to boot from USB before harddrives.


----------



## halfer (Apr 2, 2010)

Thanks Freddie, much appreciated. I tried that layout with a standard install, and got the dreaded "no space left on device" errors again. So I plumped again for the Minimal install, which installed OK as per the previous attempt, but sadly I get the same error. "Manual root filesystem specification" and a "mountroot>" prompt that does not respond to the keyboard at all.

If you have any further ideas, they shall be much appreciated. Incidentally I am intending to load a window manager of some kind so that I can manage GELI and ZFS in a GUI as much as such facilities are supported (or a web interface, if something like Webmin is available). Should 4Gb be insufficient for these things, let me know and I'll purchase an 8Gb. (I could get a small SATA drive instead I suppose - I still have three bays free after my 2 1Tb drives, and disks are quite cheap now).


----------

