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# 22.2 FreeBSD as a Guest OS

## 22.2.1 Parallels on MacOS

Parallels Desktop for Mac® is a commercial software product available for Intel® based Apple® Mac computers running Mac OS® 10.4.6 or higher. FreeBSD is a fully supported guest operating system. Once Parallels has been installed on Mac OS X, the user must configure a virtual machine and then install the desired guest operating system.

### 22.2.1.1 Installing FreeBSD on Parallels/Mac OS® X

The first step in installing FreeBSD on Mac OS X/Parallels is to create a new virtual machine for installing FreeBSD. Select FreeBSD as the Guest OS Type when prompted:

And choose a reasonable amount of disk and memory depending on your plans for this virtual FreeBSD instance. 4GB of disk space and 512MB of RAM work well for most uses of FreeBSD under Parallels:

Select the type of networking and a network interface:

Save and finish the configuration:

After your FreeBSD virtual machine has been created, you will need to install FreeBSD on it. This is best done with an official FreeBSD CDROM or with an ISO image downloaded from an official FTP site. When you have the appropriate ISO image on your local Mac filesystem or a CDROM in your Mac's CD drive, click on the disc icon in the bottom right corner of your FreeBSD Parallels window. This will bring up a window that allows you to associate the CDROM drive in your virtual machine with an ISO file on disk or with your real CDROM drive.

Once you have made this association with your CDROM source, reboot your FreeBSD virtual machine as normal by clicking the reboot icon. Parallels will reboot with a special BIOS that first checks if you have a CDROM just as a normal BIOS would do.

In this case it will find the FreeBSD installation media and begin a normal sysinstall based installation as described in Chapter 2. You may install, but do not attempt to configure X11 at this time.

When you have finished the installation, reboot into your newly installed FreeBSD virtual machine.

### 22.2.1.2 Configuring FreeBSD on Mac OS X/Parallels

After FreeBSD has been successfully installed on Mac OS X with Parallels, there are a number of configuration steps that can be taken to optimize the system for virtualized operation.

1. Set boot loader variables

   The most important step is to reduce the `kern.hz` tunable to reduce the CPU utilization of FreeBSD under the Parallels environment. This is accomplished by adding the following line to `/boot/loader.conf`:

       kern.hz=100

   Without this setting, an idle FreeBSD Parallels guest OS will use roughly 15% of the CPU of a single processor iMac®. After this change the usage will be closer to a mere 5%.

2. Create a new kernel configuration file

   You can remove all of the SCSI, FireWire, and USB device drivers. Parallels provides a virtual network adapter used by the ed(4) driver, so all other network devices except for ed(4) and miibus(4) can be removed from the kernel.

3. Setup networking

   The most basic networking setup involves simply using DHCP to connect your virtual machine to the same local area network as your host Mac. This can be accomplished by adding `ifconfig_ed0="DHCP"` to `/etc/rc.conf`. More advanced networking setups are described in Chapter 31.

## 22.2.2 FreeBSD with Xen™ on Linux

Contributed by Fukang Chen (Loader).

The Xen™ hypervisor is an open source paravirtualization product which is now supported by the commercial XenSource company. Guest operating systems are known as domU domains, and the host operating system is known as dom0. The first step in running a virtual FreeBSD instance under Linux is to install Xen for Linux dom0. The host operating system will be a Slackware Linux distribution.

### 22.2.2.1 Setup Xen 3 on Linux dom0

1. Download Xen 3.0 from XenSource

   Download xen-3.0.4_1-src.tgz from http://www.xensource.com/.

2. Unpack the tarball

       # cd xen-3.0.4_1-src
       # KERNELS="linux-2.6-xen0 linux-2.6-xenU" make world
       # make install

   > Note: To re-compile the kernel for dom0:

   >     # cd xen-3.0.4_1-src/linux-2.6.16.33-xen0
   >     # make menuconfig
   >     # make
   >     # make install

   > Older version of Xen may need to specify `make ARCH=xen menuconfig`

3. Add a menu entry into Grub menu.lst

   Edit `/boot/grub/menu.lst` and add the following lines:

       title Xen-3.0.4
       root (hd0,0)
       kernel /boot/xen-3.0.4-1.gz dom0_mem=262144
       module /boot/vmlinuz-2.6.16.33-xen0 root=/dev/hda1 ro

4. Reboot your computer into Xen

   First, edit `/etc/xen/xend-config.sxp`, and add the following line:

       (network-script 'network-bridge netdev=eth0')

   Then, we can launch Xen:

       # /etc/init.d/xend start
       # /etc/init.d/xendomains start

   Our dom0 is running:

       # xm list
       Name                                      ID   Mem VCPUs      State   Time(s)
       Domain-0                                   0   256     1     r-----  54452.9

### 22.2.2.2 FreeBSD 7-CURRENT domU

Download the FreeBSD domU kernel for Xen 3.0 and disk image from http://www.fsmware.com/

- kernel-current

- mdroot-7.0.bz2

- xmexample1.bsd

Put the configuration file `xmexample1.bsd` into `/etc/xen/` and modify the related entries about where the kernel and the disk image are stored. It should look like the following:

    kernel = "/opt/kernel-current"
    memory = 256
    name = "freebsd"
    vif = [ '' ]
    disk = [ 'file:/opt/mdroot-7.0,hda1,w' ]
    #on_crash    = 'preserve'
    extra = "boot_verbose"
    extra += ",boot_single"
    extra += ",kern.hz=100"
    extra += ",vfs.root.mountfrom=ufs:/dev/xbd769a"

The `mdroot-7.0.bz2` file should be uncompressed.

Next, the __xen_guest section in `kernel-current` needs to be altered to add the VIRT_BASE that Xen 3.0.3 requires:

    # objcopy kernel-current -R __xen_guest
    # perl -e 'print "LOADER=generic,GUEST_OS=freebsd,GUEST_VER=7.0,XEN_VER=xen-3.0,BSD_SYMTAB,VIRT_BASE=0xC0000000\x00"' > tmp
    # objcopy kernel-current --add-section __xen_guest=tmp

    # objdump -j __xen_guest -s kernel-current

    kernel-current:     file format elf32-i386

    Contents of section __xen_guest:
     0000 4c4f4144 45523d67 656e6572 69632c47  LOADER=generic,G
     0010 55455354 5f4f533d 66726565 6273642c  UEST_OS=freebsd,
     0020 47554553 545f5645 523d372e 302c5845  GUEST_VER=7.0,XE
     0030 4e5f5645 523d7865 6e2d332e 302c4253  N_VER=xen-3.0,BS
     0040 445f5359 4d544142 2c564952 545f4241  D_SYMTAB,VIRT_BA
     0050 53453d30 78433030 30303030 3000      SE=0xC0000000.

We are, now, ready to create and launch our domU:

    # xm create /etc/xen/xmexample1.bsd -c
    Using config file "/etc/xen/xmexample1.bsd".
    Started domain freebsd
    WARNING: loader(8) metadata is missing!
    Copyright (c) 1992-2006 The FreeBSD Project.
    Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
    The Regents of the University of California. All rights reserved.
    FreeBSD 7.0-CURRENT #113: Wed Jan  4 06:25:43 UTC 2006
        kmacy@freebsd7.gateway.2wire.net:/usr/home/kmacy/p4/freebsd7_xen3/src/sys/i386-xen/compile/XENCONF
    WARNING: DIAGNOSTIC option enabled, expect reduced performance.
    Xen reported: 1796.927 MHz processor.
    Timecounter "ixen" frequency 1796927000 Hz quality 0
    CPU: Intel(R) Pentium(R) 4 CPU 1.80GHz (1796.93-MHz 686-class CPU)
      Origin = "GenuineIntel"  Id = 0xf29  Stepping = 9
      Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,
      DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
      Features2=0x4400<CNTX-ID,<b14>>
    real memory  = 265244672 (252 MB)
    avail memory = 255963136 (244 MB)
    xc0: <Xen Console> on motherboard
    cpu0 on motherboard
    Timecounters tick every 10.000 msec
    [XEN] Initialising virtual ethernet driver.
    xn0: Ethernet address: 00:16:3e:6b:de:3a
    [XEN]
    Trying to mount root from ufs:/dev/xbd769a
    WARNING: / was not properly dismounted
    Loading configuration files.
    No suitable dump device was found.
    Entropy harvesting: interrupts ethernet point_to_point kickstart.
    Starting file system checks:
    /dev/xbd769a: 18859 files, 140370 used, 113473 free (10769 frags, 12838 blocks, 4.2% fragmentation)
    Setting hostname: demo.freebsd.org.
    lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
          inet6 ::1 prefixlen 128
          inet6 fe80::1%lo0 prefixlen 64 scopeid 0x2
          inet 127.0.0.1 netmask 0xff000000
    Additional routing options:.
    Mounting NFS file systems:.
    Starting syslogd.
    /etc/rc: WARNING: Dump device does not exist.  Savecore not run.
    ELF ldconfig path: /lib /usr/lib /usr/lib/compat /usr/X11R6/lib /usr/local/lib
    a.out ldconfig path: /usr/lib/aout /usr/lib/compat/aout /usr/X11R6/lib/aout
    Starting usbd.
    usb: Kernel module not available: No such file or directory
    Starting local daemons:.
    Updating motd.
    Starting sshd.
    Initial i386 initialization:.
    Additional ABI support: linux.
    Starting cron.
    Local package initialization:.
    Additional TCP options:.
    Starting background file system checks in 60 seconds.

    Sun Apr  1 02:11:43 UTC 2007

    FreeBSD/i386 (demo.freebsd.org) (xc0)

    login:

The domU should run the FreeBSD 7.0-CURRENT kernel:

    # uname -a
    FreeBSD demo.freebsd.org 7.0-CURRENT FreeBSD 7.0-CURRENT #113: Wed Jan  4 06:25:43 UTC 2006
    kmacy@freebsd7.gateway.2wire.net:/usr/home/kmacy/p4/freebsd7_xen3/src/sys/i386-xen/compile/XENCONF  i386

The network can now be configured on the domU. The FreeBSD domU will use a specific interface called `xn0`:

    # ifconfig xn0 10.10.10.200 netmask 255.0.0.0
    # ifconfig
    xn0: flags=843<UP,BROADCAST,RUNNING,SIMPLEX> mtu 1500
        inet 10.10.10.200 netmask 0xff000000 broadcast 10.255.255.255
        ether 00:16:3e:6b:de:3a
    lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
          inet6 ::1 prefixlen 128
          inet6 fe80::1%lo0 prefixlen 64 scopeid 0x2
          inet 127.0.0.1 netmask 0xff000000

On dom0 Slackware, some Xen dependant network interfaces should show up:

    # ifconfig
    eth0      Link encap:Ethernet  HWaddr 00:07:E9:A0:02:C2
              inet addr:10.10.10.130  Bcast:0.0.0.0  Mask:255.0.0.0
              UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
              RX packets:815 errors:0 dropped:0 overruns:0 frame:0
              TX packets:1400 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:0
              RX bytes:204857 (200.0 KiB)  TX bytes:129915 (126.8 KiB)

    lo        Link encap:Local Loopback
              inet addr:127.0.0.1  Mask:255.0.0.0
              UP LOOPBACK RUNNING  MTU:16436  Metric:1
              RX packets:99 errors:0 dropped:0 overruns:0 frame:0
              TX packets:99 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:0
              RX bytes:9744 (9.5 KiB)  TX bytes:9744 (9.5 KiB)

    peth0     Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF
              UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
              RX packets:1853349 errors:0 dropped:0 overruns:0 frame:0
              TX packets:952923 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:1000
              RX bytes:2432115831 (2.2 GiB)  TX bytes:86528526 (82.5 MiB)
              Base address:0xc000 Memory:ef020000-ef040000

    vif0.1    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF
              UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
              RX packets:1400 errors:0 dropped:0 overruns:0 frame:0
              TX packets:815 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:0
              RX bytes:129915 (126.8 KiB)  TX bytes:204857 (200.0 KiB)

    vif1.0    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF
              UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
              RX packets:3 errors:0 dropped:0 overruns:0 frame:0
              TX packets:2 errors:0 dropped:157 overruns:0 carrier:0
              collisions:0 txqueuelen:1
              RX bytes:140 (140.0 b)  TX bytes:158 (158.0 b)

    xenbr1    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF
              UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
              RX packets:4 errors:0 dropped:0 overruns:0 frame:0
              TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
              collisions:0 txqueuelen:0
              RX bytes:112 (112.0 b)  TX bytes:0 (0.0 b)

    # brctl show
    bridge name     bridge id           STP enabled         interfaces
    xenbr1          8000.feffffffffff   no                  vif0.1
                                                            peth0
                                                            vif1.0

## 22.2.3 Virtual PC on Windows®

Virtual PC for Windows® is a Microsoft® software product available for free download. See system requirements. Once Virtual PC has been installed on Microsoft Windows, the user must configure a virtual machine and then install the desired guest operating system.

### 22.2.3.1 Installing FreeBSD on Virtual PC/Microsoft® Windows

The first step in installing FreeBSD on Microsoft Windows /Virtual PC is to create a new virtual machine for installing FreeBSD. Select Create a virtual machine when prompted:

And select Other as the Operating system when prompted:

Then, choose a reasonable amount of disk and memory depending on your plans for this virtual FreeBSD instance. 4GB of disk space and 512MB of RAM work well for most uses of FreeBSD under Virtual PC:

Save and finish the configuration:

Select your FreeBSD virtual machine and click Settings, then set the type of networking and a network interface:

After your FreeBSD virtual machine has been created, you will need to install FreeBSD on it. This is best done with an official FreeBSD CDROM or with an ISO image downloaded from an official FTP site. When you have the appropriate ISO image on your local Windows filesystem or a CDROM in your CD drive, double click on your FreeBSD virtual machine to boot. Then, click CD and choose Capture ISO Image... on Virtual PC window. This will bring up a window that allows you to associate the CDROM drive in your virtual machine with an ISO file on disk or with your real CDROM drive.

Once you have made this association with your CDROM source, reboot your FreeBSD virtual machine as normal by clicking the Action and Reset. Virtual PC will reboot with a special BIOS that first checks if you have a CDROM just as a normal BIOS would do.

In this case it will find the FreeBSD installation media and begin a normal sysinstall based installation as described in Chapter 2. You may install, but do not attempt to configure X11 at this time.

When you have finished the installation, remember to eject CDROM or release ISO image. Finally, reboot into your newly installed FreeBSD virtual machine.

### 22.2.3.2 Configuring FreeBSD on Microsoft Windows/Virtual PC

After FreeBSD has been successfully installed on Microsoft Windows with Virtual PC, there are a number of configuration steps that can be taken to optimize the system for virtualized operation.

1. Set boot loader variables

   The most important step is to reduce the `kern.hz` tunable to reduce the CPU utilization of FreeBSD under the Virtual PC environment. This is accomplished by adding the following line to `/boot/loader.conf`:

       kern.hz=100

   Without this setting, an idle FreeBSD Virtual PC guest OS will use roughly 40% of the CPU of a single processor computer. After this change the usage will be closer to a mere 3%.

2. Create a new kernel configuration file

   You can remove all of the SCSI, FireWire, and USB device drivers. Virtual PC provides a virtual network adapter used by the de(4) driver, so all other network devices except for de(4) and miibus(4) can be removed from the kernel.

3. Setup networking

   The most basic networking setup involves simply using DHCP to connect your virtual machine to the same local area network as your host Microsoft Windows. This can be accomplished by adding `ifconfig_de0="DHCP"` to `/etc/rc.conf`. More advanced networking setups are described in Chapter 31.

## 22.2.4 VMware on MacOS

VMware Fusion for Mac is a commercial software product available for Intel based Apple Mac computers running Mac OS 10.4.9 or higher. FreeBSD is a fully supported guest operating system. Once VMware Fusion has been installed on Mac OS X, the user must configure a virtual machine and then install the desired guest operating system.

### 22.2.4.1 Installing FreeBSD on VMware/Mac OS X

The first step is to start VMware Fusion, the Virtual Machine Library will load. Click "New" to create the VM:

This will load the New Virtual Machine Assistant to help you create the VM, click Continue to proceed:

Select Other as the Operating System and FreeBSD or FreeBSD 64-bit, depending on if you want 64-bit support, as the Version when prompted:

Choose the Name of the VM Image and the Directory where you would like it saved:

Choose the size of the Virtual Hard Disk for the VM:

Choose the method you would like to install the VM, either from an ISO image or from a CD:

Once you click Finish, the VM will boot:

Install FreeBSD like you normally would, or by following the directions in Chapter 2:

Once the install is complete you can modify the settings of the VM, such as Memory Usage:

> Note: The System Hardware settings of the VM cannot be modified while the VM is running.

The number of CPUs the VM will have access to:

The status of the CD-Rom Device. Normally you can disconnect the CD-Rom/ISO from the VM if you will not be needing it anymore.

The last thing to change is how the VM will connect to the Network. If you want to allow connections to the VM from other machines besides the Host, make sure you choose the Connect directly to the physical network (Bridged). Otherwise Share the host's internet connection (NAT) is preferred so that the VM can have access to the Internet, but the network cannot access the VM.

After you have finished modifying the settings, boot the newly installed FreeBSD virtual machine.

### 22.2.4.2 Configuring FreeBSD on Mac OS X/VMware

After FreeBSD has been successfully installed on Mac OS X with VMware, there are a number of configuration steps that can be taken to optimize the system for virtualized operation.

1. Set boot loader variables

   The most important step is to reduce the `kern.hz` tunable to reduce the CPU utilization of FreeBSD under the VMware environment. This is accomplished by adding the following line to `/boot/loader.conf`:

       kern.hz=100

   Without this setting, an idle FreeBSD VMware guest OS will use roughly 15% of the CPU of a single processor iMac. After this change the usage will be closer to a mere 5%.

2. Create a new kernel configuration file

   You can remove all of the FireWire, and USB device drivers. VMware provides a virtual network adapter used by the em(4) driver, so all other network devices except for em(4) can be removed from the kernel.

3. Setup networking

   The most basic networking setup involves simply using DHCP to connect your virtual machine to the same local area network as your host Mac. This can be accomplished by adding `ifconfig_em0="DHCP"` to `/etc/rc.conf`. More advanced networking setups are described in Chapter 31.

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