[tahoe-dev] Tahoe-LAFS is widely misunderstood

[Scott Dial]

On 2/3/2011 1:44 AM, Chris Palmer wrote:
> Scott Dial writes:
>> % attr -g writecap .
>> URI:DIR2:xxx...:yyy...
>> % attr -g readcap .
>> URI:DIR2-RO:xxx...:yyy...
>> % attr -g verifycap .
>> URI:DIR2-Verifier:xxx...:yyy...
> 
> What platform do you do this on? On Ubuntu, attr(1) is a non-default package
> and is specific to XFS; getfattr(1) and setfattr(1) are present but the
> default ext3 configuration does not have option user_xattr.
> 

You're right. I misremembered the commands. "attr" is the XFS variation
of the same thing (except that attr prepends a "user." or "root." prefix
to the name before calling getxattr() in order to make distinct
namespaces for users and superusers). "getfattr" is the more standard
tool. So, the proper snippet should've been:

% getfattr -n readcap .
# file: .
readcap="URI:DIR2-RO:xxx...:yyy..."

And I think it's quite powerful to be able to do:

% tahoe check `getfattr -n readcap --only-values somefile`
Summary: Healthy
  storage index: qggq5w4ynbxo6x2ns3ydv3uyq4
  good-shares: 12 (encoding is 3-of-12)
  wrong-shares: 0

-- 
Scott Dial
scott at scottdial.com
scodial at cs.indiana.edu