Re: Recursion limits

[Colin Percival <cperciva@tarsnap.com>]

On 05/25/15 01:44, Arthur Chance wrote:
> On 24/05/2015 23:16, Colin Percival wrote:
>> On 05/24/15 11:18, Bob wrote:
>>> I recently attempted a restore and discovered that my backup didn't go down
>>> the full directory tree for a couple of items. Is there a limit to the depth
>>> tarsnap will recurse?
>>
>> Not one you should run into.  The only limits I'm aware of are the inevitable
>> ones (e.g., "paths must fit into RAM").
>>
>> Can you reproduce the scenario with `tarsnap -c -v --dry-run` (which should
>> list the objects which would be archived but not actually create an archive)?
> 
> A quick look at man libarchive-formats shows:
> 
> ustar  The libarchive library can both read and write this format.  This
>        format has the following limitations:
>        ·   Device major and minor numbers are limited to 21 bits.  Nodes
>            with larger numbers will not be added to the archive.
>        ·   Path names in the archive are limited to 255 bytes.  (Shorter
>                  if there is no / character in exactly the right place.)
> 
> I don't know if ustar format is the one Colin uses, but do the missing files
> have pathnames longer than 255 chars?

Tarsnap uses the (bsdtar default) "restricted pax", so it should handle longer
file names via the pax extension to ustar.

-- 
Colin Percival
Security Officer Emeritus, FreeBSD | The power to serve
Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid