Re: Corrupt/missing store items

[Jack Hill <jackhill@jackhill.us>]

On Tue, 22 Jun 2021, Ricardo Wurmus wrote:

> Jack Hill <jackhill@jackhill.us> writes:
>
> What happens if you try “guix build --check --no-grafts 
> /gnu/store/zkhymfsbrv0s4y7l778g78k6y65nidxd-gnutls-3.6.16.drv” or similar? 
> The database probably states that 
> /gnu/store/jlk67v3nddhv0z963wfvahk8fc8gqcz8-gnutls-3.6.16 has already been 
> built, so with “--check” you might be able to make it build it again.

`guix gc --verify=repair` fixed the problem, so I won't be able to test 
this (unless this recurs, but I hope it doesn't).

>> So Guix think's it's sucessfully built gnutls, but it's still not
>> present in the store. I've also tried copying the store items from
>> other hosts. No luck so far…
>
> How did that fail?

I didn't capture verbose output, but I believe nothing was sent because 
the problematic host reported it already had that item.

> How could the directory have disappeared?  Guix appears to be very surprised 
> that the directory is missing.

Apologies for leaving out more details about this host earlier. The 
filesystem is btrfs and its a virtual machine running in someone else's VM 
cluster. I had to reset and boot into older generations a few times before 
I noticed the problem because of a misconfiguration I made. Some of these 
older generation involved downgrading the kernel from 5.12 to 5.11. I 
suppose that could have caused file system corruption, although I would 
not have expected the store to be written to at the time of the resets.

Best,
Jack