I have my Linux/Debian/Sid amd64 (with i7 3770K, 16Gb RAM, 1 SSD + 2 hard disks) PC with xen (notably I have installed a package xen-linux-system-amd64), so  sudo xen list Name                                        ID   Mem VCPUs State   Time(s) Domain-0                                     0 16016     8     r-----    2634.8I am understanding that the Dom0 is my Linux 4.0 kernel & system; I have xen-hypervisor-4.5-amd...I have a disk with two partitions for FreeBSDsudo fdisk -l /dev/sddDisk /dev/sdd: 465.8 GiB, 500106780160 bytes, 976771055 sectorsUnits: sectors of 1 * 512 = 512 bytesSector size (logical/physical): 512 bytes / 512 bytesI/O size (minimum/optimal): 512 bytes / 512 bytesDisklabel type: dosDisk identifier: 0x624aeae3Device     Boot     Start       End   Sectors  Size Id Type/dev/sdd1            2048 754976767 754974720  360G 83 Linux/dev/sdd2       754976768 773851135  18874368    9G 82 Linux swap / Solaris/dev/sdd3       773851136 792725503  18874368    9G b8 BSDI swap/dev/sdd4       792725504 976771054 184045551 87.8G b7 BSDI fs(BTW, this is not my system disk; /dev/sdd1 is for my /xtra Linux ext4 file system, and dev/sdd2 is my second swap partition)I would like to run FreeBSD, probably only on the command line since I don't need to run X11 server under FreeBSD, (preferably FreeBSD 10.1 for x86-64 architecture) under xen using /dev/sdd4 for its root (and only) filesystem and /dev/sdd3 for its swap area. But I am not sure of how to proceed next.Should I download FreeBSD-10.1-RELEASE-amd64-bootonly.iso or what? What are the next steps to run it under xen? The http://wiki.xen.org/wiki/How_to_Install_a_FreeBSD_domU_on_a_Linux_Host page is not helpful enough (& https://www.freebsd.org/doc/handbook/virtualization-guest.html don't mention xen)FWIW, I am an old Unixer (my first Unix was SunOS3.2 on Sun3/160 in the mid 1980s) and my main motivation for trying FreeBSD is to check that my MELT software (a GPLv3 plugin for recent GCC to easily extend and customize GCC in a Lisp-like language) can be used on FreeBSD.
run FreeBSD 10 (as guest) under Xen on Linux
linux;freebsd;xen
Since I couldn't find an accurate guide for setting up FreeBSD 10 as a domU under Xen either, I wrote my own. I believe you're using a newer OS release and Xen version than me, but the process should be similar. Here's the gist:Download a FreeBSD 10 ISO (I used FreeBSD-10.1-RELEASE-amd64-disc1.iso) and put console=comconsole in its /boot/loader.conf to let you install over a serial console. If you know how to use VNC instead, that should be fine too -- in that case, ignore what I say about using serial. The FreeBSD handbook has detailed instructions on extracting and recreating the ISO.Allocate disk partitions and MAC addresses, and create your domU configuration. Here's mine:memory = 1024name = eagle# PVHVM stuffbuilder = hvmkernel = hvmloaderboot = dcvif = [ 'mac=00:16:3E:01:AB:23' ]disk = [ 'phy:/dev/solid-state/eagle-disk,hda,w',         'file:/virt/iso/FreeBSD-10.1-RELEASE-amd64-headless.iso,hdb:cdrom,r'       ]# Necessary for getting the serial console in `xm console`serial = ptyStart the domU and install as normal. At the mountroot prompt after the bootloader but before the installer, use ? to enumerate your options -- you probably want something like cd9660:cd0.At the end of the installation process, choose to open a shell in the newly-installed system and put console=comconsole in its /boot/loader.conf as well. Then, shut down the domU.In your domU configuration file, change boot = dc to boot = c to boot from the disk you installed to rather than the ISO. You can also remove the ISO's disk entry if you want.Start the domU -- at this point, you should be all set.