> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/ask/flat/chapter-16-advanced-freebsd-installation/di-16.1-jie-an-zhuang-shuang-xi-tong-xian-an-zhuang-freebsd.md). # 16.1 Dual-Boot Installation (FreeBSD Installed First) This section covers deploying FreeBSD and Windows as a dual-boot system on the same physical device, installing FreeBSD first and then Windows. ## Installing FreeBSD 14.2-RELEASE First, install the FreeBSD 14.2-RELEASE system. Unless otherwise specified, default settings and parameters are used throughout. ![FreeBSD installation interface](/files/bd9TtbUIUoLiA5fLoMGb) ![FreeBSD installation interface](/files/intq4WJAyphC8sJnikTb) > **Tip** > > If you set `P Partition Scheme` to `GPT (UEFI)` here instead of other options (only older computers need to select `GPT (BIOS+UEFI)` and similar options), the subsequent partitioning and system update process will be simpler, and 4K alignment can also be achieved. ![Partition scheme selection](/files/Kypj1PMO3h0goNLvDyX3) Here you need to set a larger temporary swap partition. This value should be the sum of the planned swap partition size and the Windows system partition size. This is done so that when installing Windows later, you can directly use this space without additional partitioning operations. In this section, the swap partition size is 8 GB, and the remaining 200 GB of space is reserved for Windows. Please adjust the value of `S Swap Size`. > **Note** > > The `Partition Scheme` partition table should be set to `GPT (uefi)`! Otherwise, an extra `freebsd-boot` partition will be created. ![Swap partition size setting](/files/aGAWJPYbkoDvZMgD0WYM) List the system disk partition layout: ```sh # gpart show => 9 639659 cd0 MBR (1.2G) 9 639659 - free - (1.2G) => 9 639659 iso9660/14_2_RELEASE_AMD64_CD MBR (1.2G) 9 639659 - free - (1.2G) => 40 629145520 nda0 GPT (300G) 40 532480 1 efi (260M) 533544 984 - free - (492K) 534528 436207616 3 freebsd-swap (208G) 436742144 192401408 4 freebsd-zfs (92G) 629143552 2008 - free - (1.0M) ``` Display swap partition and swap file usage (in MB/GB): ```sh # swapinfo -mh Device Size Used Avail Capacity /dev/nda0p3 208G 0B 208G 0% ``` The swap partition size is the configured 208 GB (of which 200 GB is reserved for the Windows operating system). Edit the **/etc/fstab** file and add `#` at the beginning of the swap line to comment it out (in this example, it is the third line). This prevents the system from mounting this swap partition at boot, preparing for the subsequent Windows installation: ```sh # Device Mountpoint FStype Options Dump Pass# /dev/gpt/efiboot0 /boot/efi msdosfs rw 2 2 #/dev/nda0p3 none swap sw 0 0 ``` ## Installing Windows 11 After FreeBSD is installed, install the Windows system. Insert the Windows installation media, select booting from this media in the firmware settings, and begin installing Windows. At this point, the installer will recognize the existing partition structure on the hard disk, and you can use the previously reserved space. ![Windows installation partition interface](/files/6atbexL9LE2AiSGEDgXq) In the partition interface, delete (Delete Partition) the entire 208 GB swap partition (in this example, "Disk 0 Partition 3"), since this space has been reserved for Windows. ![Deleting the swap partition](/files/GzbKA7fEwpyDxvAax6RT) Then select Create Partition. If an error message appears, select Refresh. The Windows installer will automatically create the required partitions on the unallocated space, including the MSR partition, system partition, and recovery partition. Select the 208 GB "Disk 0 Unallocated Space", confirm, and continue the installation. ![Selecting unallocated space to install Windows](/files/zoer3cxwRNasxuXZxiIj) ## Restoring the Swap Partition After Windows is installed, restore the FreeBSD swap partition. The previously reserved 208 GB of space includes 8 GB for the swap partition. The following operations use the tool [DiskGenius](https://www.diskgenius.com/). ![DiskGenius main interface](/files/bAKewR5tFKdviAB0L6km) Launch DiskGenius and adjust the C drive partition size to release 8 GB of unallocated space. After Windows installation, the C drive occupies most of the reserved space; shrinking 8 GB from the end of the C drive is sufficient. ![Shrinking the C drive](/files/mJWTec8W6Cyu5NwQcbIw) Set the partition type of this 8 GB space to `FreeBSD Swap partition` and save the changes. This step marks the newly created swap partition with a type that FreeBSD can recognize. ![Formatting the swap partition](/files/etJYwAll9zD3MyJfzN9B) ![Saving partition changes](/files/hZlLwIPCcPyxDdJ9L2b4) Return to FreeBSD and check the disk partition layout: ```sh # gpart show => 34 629145533 nda0 GPT (300G) 34 6 - free - (3.0K) 40 532480 1 efi (260M) 533544 984 - free - (492K) 534528 32768 3 ms-reserved (16M) 567296 417953792 4 ms-basic-data (199G) 418521088 16777216 5 freebsd-swap (8.0G) 435298304 1441792 6 ms-recovery (704M) 436740096 2048 - free - (1.0M) 436742144 192401408 7 freebsd-zfs (92G) 629143552 2015 - free - (1.0M) ``` Partition 5 (`nda0p5`) is the newly created swap partition. Enable this swap partition: ```sh # swapon /dev/nda0p5 ``` No error output indicates the operation was successful, and the system has recognized and is using this swap partition. Edit the **/etc/fstab** file, remove the comment symbol `#` from the beginning of the swap line, and change the partition to the correct value. The configuration in this example is shown on the third line: ```sh # Device Mountpoint FStype Options Dump Pass# /dev/gpt/efiboot0 /boot/efi msdosfs rw 2 2 /dev/nda0p5 none swap sw 0 0 ``` After rebooting, check the current swap partition status again: ```sh # swapinfo -mh Device Size Used Avail Capacity /dev/nda0p5 8.0G 0B 8.0G 0% ``` List all ZFS pools and their status in the system: ```sh # zpool list NAME SIZE ALLOC FREE CKPOINT EXPANDSZ FRAG CAP DEDUP HEALTH ALTROOT zroot 91.5G 922M 90.6G - - 0% 0% 1.00x ONLINE - # zfs list NAME USED AVAIL REFER MOUNTPOINT zroot 922M 87.8G 96K /zroot zroot/ROOT 919M 87.8G 96K none zroot/ROOT/default 919M 87.8G 919M / zroot/home 224K 87.8G 96K /home zroot/home/ykla 128K 87.8G 128K /home/ykla zroot/tmp 104K 87.8G 104K /tmp zroot/usr 288K 87.8G 96K /usr zroot/usr/ports 96K 87.8G 96K /usr/ports zroot/usr/src 96K 87.8G 96K /usr/src zroot/var 668K 87.8G 96K /var zroot/var/audit 96K 87.8G 96K /var/audit zroot/var/crash 96K 87.8G 96K /var/crash zroot/var/log 188K 87.8G 188K /var/log zroot/var/mail 96K 87.8G 96K /var/mail zroot/var/tmp 96K 87.8G 96K /var/tmp ``` --- # Agent Instructions This documentation is published with GitBook. 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