Dualboot and ZFS

[Manish Jain]

On 01/15/18 15:20, Manish Jain wrote:
> 
> 
> On 01/15/18 10:43, Victor Sudakov wrote:
>> Dear Colleagues,
>>
>> I have a box with dual boot: Windows and FreeBSD/UFS:
>>
>> $ gpart show ada0
>> =>       63  976773105  ada0  MBR  (466G)
>>            63       1985        - free -  (993K)
>>          2048  293029888     1  ntfs  [active]  (140G)
>>     293031936  598958080     2  ntfs  (286G)
>>     891990016   83886080     3  freebsd  (40G)
>>     975876096     897072        - free -  (438M)
>>
>> $ gpart show ada0s3
>> =>       0  83886080  ada0s3  BSD  (40G)
>>            0  75497472       1  freebsd-ufs  (36G)
>>     75497472   8388607       2  freebsd-swap  (4.0G)
>>     83886079         1          - free -  (512B)
>>
>> $
>>
>> boot0 handles the OS selection, everything works just fine.
>>
>> Can I install FreeBSD with root-on-zfs into ada0s3 somehow?
>>
> 
> Hi Victor,
> 
> Yes, you can. But you will need a spare slice somewhere - another disk
> (SATA / USB). If the used potion of your ada0s3a is small, you can even
> use a USB pen drive.


Actually, if you don't care about your data on ada0s3a (or are willing 
to back it up to another disk), you can even use ada0s4 as the spare slice.

The strategy for this would be to install FreeBSD-UFS afresh again, this 
time creating two slices ada0s3 and ada0s4 (both freebsd). Size ada0s3 
as 36G and s4 as 4G. Install into s4, not s3.

Boot into s4 and install rsync via pkg.

Then use the steps previously mentioned to rsync from ada0s4a-ufs to 
ad0s3a-zfs.

Once the sync to s3 is done, boot into s3. And then you can use s4a as a 
swap partition.

Regards,
Manish Jain