[gentoo-user] [OT] ext3 file permissions on a USB drive

[gentoo-user] [OT] ext3 file permissions on a USB drive

[»Q«]

I promise I googled.  I found the question asked quite a bit, but never
found a solution.  This isn't a Gentoo-specific question, so I marked
it [OT].

I have a USB HDD, using ext3, and I'd like all users to be able to have
full permissions for any file on it.  It's *not* a problem to mount it
rw for all users;  I mention this because googling turned up a lot of
people mistaking that question for the one I want to ask.

The problem is that if user A on machine X creates a file on the drive,
it has access permissions 644, which makes it impossible for user B on
machine Y to modify the file.  (User A and user B are both me, but with
different UIDs on the different machines.)

What I'd like is for all files created on the drive to have
permissions 666, but I don't see any way to override the system umask
(0022) for only this drive.  I saw somewhere suggested that setting
the device node and the mountpoint permissions both to 666 would do
that, but it doesn't work for me (and I don't know why it would for
anyone).

As it is now, I have to occasionally use '# chmod -R 666' on the
entire drive before I can work with files on it.

If I reformat the disk as vfat, I could use the umask mount option for
vfat, but if possible I'd rather keep using ext3.

-- 
»Q«
     Kleeneness is next to Gödelness.

Re: [gentoo-user] [OT] ext3 file permissions on a USB drive

[Neil Bothwick]

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On Sun, 15 Mar 2009 16:16:05 -0500, »Q« wrote:

> What I'd like is for all files created on the drive to have
> permissions 666, but I don't see any way to  override
> the system umask (0022) for only this drive.

If you don't want to change the system umask, and you probably don't,
ACLs are the best way to do what you want.


-- 
Neil Bothwick

Stupid user error. Terminate user (Y/n) ?

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[gentoo-user] Re: [OT] ext3 file permissions on a USB drive

[»Q«]

In <20090315220009.6a701622@krikkit.digimed.co.uk>,
Neil Bothwick <neil@digimed.co.uk> wrote:

> On Sun, 15 Mar 2009 16:16:05 -0500, »Q« wrote:
> 
> > What I'd like is for all files created on the drive to have
> > permissions 666, but I don't see any way to  override
> > the system umask (0022) for only this drive.  
> 
> If you don't want to change the system umask, and you probably don't,

I definitely don't!

> ACLs are the best way to do what you want.

I was really afraid you'd say that, heh.  ACLs are on my to-learn-about
list, but were pretty far down it.  I guess they just moved up a few
notches.

Seriously, thanks for the pointer.  If I do decide to try that approach,
I'll post back hw it worked out.

-- 
»Q«
     Kleeneness is next to Gödelness.

Re: [gentoo-user] Re: [OT] ext3 file permissions on a USB drive

[Neil Bothwick]

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On Mon, 16 Mar 2009 00:26:55 -0500, »Q« wrote:

> > ACLs are the best way to do what you want.  
> 
> I was really afraid you'd say that, heh.  ACLs are on my to-learn-about
> list, but were pretty far down it.  I guess they just moved up a few
> notches.

I felt the same until I was forced into looking at ACLs. They're
quite straightforward really.


-- 
Neil Bothwick

Crayons can take you more places than starships. * Guinan

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Re: [gentoo-user] [OT] ext3 file permissions on a USB drive

[Dan Farrell]

On Sun, 15 Mar 2009 16:16:05 -0500
»Q« <boxcars@gmx.net> wrote:

> The problem is that if user A on machine X creates a file on the
> drive, it has access permissions 644, which makes it impossible for
> user B on machine Y to modify the file.  (User A and user B are both
> me, but with different UIDs on the different machines.)

You could use ACL as has been  suggested; you could also just set the
uids of the (same) user on these machines to the same thing.

Using the same uid across boxes is a really good idea if you have users
on each box anyway.  

Re: [gentoo-user] [OT] ext3 file permissions on a USB drive

[Paul Hartman]

On Mon, Mar 16, 2009 at 2:59 PM, Dan Farrell <dan@spore.ath.cx> wrote:
> On Sun, 15 Mar 2009 16:16:05 -0500
> »Q« <boxcars@gmx.net> wrote:
>
>> The problem is that if user A on machine X creates a file on the
>> drive, it has access permissions 644, which makes it impossible for
>> user B on machine Y to modify the file.  (User A and user B are both
>> me, but with different UIDs on the different machines.)
>
> You could use ACL as has been  suggested; you could also just set the
> uids of the (same) user on these machines to the same thing.
>
> Using the same uid across boxes is a really good idea if you have users
> on each box anyway.

I wonder if you could share and mount it using samba/cifs or
something, which allows fudging of the UID/GID ...