migrating R3.1 appvm to R4.0 manually

[Jake]

Hello list,

i need to migrate a R3.1 appvm to R4.0 manually.  due to this appvm
having overfilled the hard drive of a R3.1 installation, i had to
migrate the contents of /var/lib/qubes/appvm/<this appvm> to another
drive.  i have verified {private,volatile}.img were copied without
error, but i cannot get the appvm to show up under a new R4.0
installation with these files manually copied to
/var/lib/qubes/appvm/<this appvm>, in dom0.

can someone give me input on what i need to do to get this appvm to
register/start on R4.0? i am confident there is a way to do this, but i
do not know what is required.

regards,

jake

[Yuraeitha]

I do by no means know if this is safe, but I do believe it should work.
Essentially try create a VM in the same name as your old VM, then shut it down. Go into your /var/lib/qubes/appvm/<this appvm> and then manually replace the data. Then try start the AppVM, and see if it works.

I don't believe it can hurt to try though, what I wonder about is whether it can cause data corruption, but it might just be me being too careful. You may want to keep that 3.1. AppVM data as a backup if you ever encounter data-corruption.

You can also move all your AppVM content from old AppVM to a new fresh AppVM, and then hash-check your files integrity in Qubes 3.1. (if you can still do that) and the files in your new AppVM. At least, then there will be no remains left from the old 3.1. AppVM. It might be "over-protective" to go that far though, this is my lack of knowledge speaking to taking extra safety measures.

[awokd]

On Mon, March 19, 2018 7:04 pm, Yuraeitha wrote:
> On Monday, March 19, 2018 at 7:45:30 PM UTC+1, Jake wrote:
>
>> Hello list,
>>
>>
>> i need to migrate a R3.1 appvm to R4.0 manually.  due to this appvm
>> having overfilled the hard drive of a R3.1 installation, i had to
>> migrate the contents of /var/lib/qubes/appvm/<this appvm> to another
>> drive.  i have verified {private,volatile}.img were copied without
>> error, but i cannot get the appvm to show up under a new R4.0
>> installation with these files manually copied to
>> /var/lib/qubes/appvm/<this appvm>, in dom0.
>>
>>
>> can someone give me input on what i need to do to get this appvm to
>> register/start on R4.0? i am confident there is a way to do this, but i
>> do not know what is required.
>>
>> regards,
>>
>> jake
>

> You can also move all your AppVM content from old AppVM to a new fresh
> AppVM, and then hash-check your files integrity in Qubes 3.1. (if you can
> still do that) and the files in your new AppVM. At least, then there will
> be no remains left from the old 3.1. AppVM. It might be "over-protective"
> to go that far though, this is my lack of knowledge speaking to taking
> extra safety measures.

I think a variation of this will be the most straight-forward way to do
it, since 4.0 uses LVM instead of those .img files.

1. Create temp VM, copy .img files inside and mount them.
2. Create perm VM
3. qvm-copy files from temp to perm
4. Delete temp VM

[Yuraeitha]

That's a good idea, that removes the uncertainty part of it all when directly accessing the img files manually.