HD permissions stay put

[Ian Malone]

On 3 July 2011 22:46, JD <jd1008 at gmail.com> wrote:
> On 07/03/2011 02:26 PM, Petrus de Calguarium wrote:
>> JD wrote:
>>
>>>> Machine one..johan 1000:1000
>>>> Machine two ..johan 500:500
>> This is the problem I had with Debian and friends.
>>
>> Fedora starts users at 500, while Debian&c uses 1000. So, if you use the same
>> username on both, you now have the same user with both 500 and 1000 uid. When
>> you log back into fedora (at least that is what happened to me), my stuff is
>> now changed to user 500, or was it 501. It was a real mess! And the problem
>> with Debian systems is that I could not find a way to get users to start at
>> 500, so as to be the same as Fedora. It was a mess, so I decided no longer to
>> mount user data to non-Fodora systems.
>>
> I think you have exposed a very interesting problem.
> It means that if, for example, /home was created on
> separate partition on a fedora machine,
> and you decide to share that home mount point with
> other linux/es /, (many people have multiple versions of
> linux installed on same machine), then there will be
> this incompatibility as far as uid's and gid's are concerned.
>
> I wonder why the distros do not agree to starting with
> the same uid/gid number for first user account.
>

It wouldn't really help: what happens when you have multiple users on
each system (and even for a home desktop system this isn't unusual)?
You just have to keep the account ID synced when you create them,
which is usually quite easy, but does require you to be aware of the
need to do it. Even more of an issue once you start dealing with NFS.
As Patrick O'Callaghan says then you start thinking about LDAP etc.,
but it's a pain to set up and doesn't address the situation of
multi-boot systems (though that's a small number). In theory
installers could check this stuff and offer to synchronise uids for
you (GIDs might be a bit more of a problem since lower ones are often
used for system things, room for some standardisation there if it
hasn't already happened, but those things tend to be restricted to
/etc and other directories that wouldn't be shared anyway). I wonder
if there are similar problems with Selinux contexts or if those are
standardised enough to start with (and, again, the funny ones will
probably not be in directories shared between systems).

-- 
imalone