Re: [ubuntu-uk] Some advice - permissions
2009/5/25 Lucy : > 2009/5/20 Neil Greenwood : >> If you create more than one user in each installation, you have to >> create them in the same order so that they get the same UIDs - if you >> don't, this is the only time you should have to use the chown/chgrp >> commands, although chown will change group too (just to confuse you >> even more!). > > FWIW, chown won't change the group by default. e.g > > chown -R fred /home/bob > > Will change the ownership of all bob's files to fred, but not the group. > Whereas > > chown -R fred:fred /home/bob > > or, as a shortcut: > > chown -R fred: /home/bob > > Will change both the owner and the groups. > > -- > ubuntu-uk@lists.ubuntu.com > https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk > https://wiki.ubuntu.com/UKTeam/ > Lucy, Thanks for clarifying. That's what I'd said in my head, but re-reading it I wasn't as clear as I wanted to be. :-) Cofion, Neil. -- ubuntu-uk@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk https://wiki.ubuntu.com/UKTeam/
Re: [ubuntu-uk] Some advice - permissions
2009/5/20 Neil Greenwood : > If you create more than one user in each installation, you have to > create them in the same order so that they get the same UIDs - if you > don't, this is the only time you should have to use the chown/chgrp > commands, although chown will change group too (just to confuse you > even more!). FWIW, chown won't change the group by default. e.g chown -R fred /home/bob Will change the ownership of all bob's files to fred, but not the group. Whereas chown -R fred:fred /home/bob or, as a shortcut: chown -R fred: /home/bob Will change both the owner and the groups. -- ubuntu-uk@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk https://wiki.ubuntu.com/UKTeam/
Re: [ubuntu-uk] Some advice - permissions
2009/5/20 Paul Sutton : > regarding point B, if you create a new users then won't this cause > permission issues, as say old system has > > /home/paul > > and the new install has /home/paul2 > > the files will still belong to paul, and will need to have ownership > changed (chown) and (chgrp) so you can read as the new user. > > Just a thought, but this is something to perhaps consider, comments > welcome in case I have perhaps mis understood something. > > I have my files on a different partition which makes sense, but you also > make a good point regarding back ups. > Hi Paul, It gets a bit more complicated than this! The filesystem stores the user and group for each file as a numeric ID. Then the /etc/passwd and /etc/groups files provide a cross-reference for converting the numeric ID into a user (or group) name and vice versa. When you create a user on a new installation, it uses the first free numeric ID above a fixed offset (which I believe is 1000 for Ubuntu). So in the original installation, user 'paul' probably has a numeric ID (UID) of 1000. In the new installation, user 'paul2' probably has a UID of 1000 too, since the new installation knows nothing about the previous user called 'paul', apart from some files in the /home partition belonging to a UID of 1000. If you create more than one user in each installation, you have to create them in the same order so that they get the same UIDs - if you don't, this is the only time you should have to use the chown/chgrp commands, although chown will change group too (just to confuse you even more!). Clear as mud? Cofion/Regards, Neil. -- ubuntu-uk@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk https://wiki.ubuntu.com/UKTeam/
Re: [ubuntu-uk] Some advice - permissions
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Matthew Daubney wrote: > On Tue, 2009-05-19 at 11:01 +0100, Sean Miller wrote: >> Should have broadband again today, so going to download an ISO and >> endeavour to fix my broken Jaunty. >> >> Now, a week or so ago somebody said to me that to preserve my data I >> simply asked it not to format the partition, which would leave /home >> intact. >> >> Two questions :- >> >> a. are there any potential side-effects to this (eg. files left from >> the corrupt version that interfere with the new one)? >> b. should I set up the default username as something different to the >> original (ie. if I use the same username could it decide to delete and >> recreate the user, thus blanking the home directory)? >> > > Hi Shaun, > > As with anything it'll be best to back up anything important first > (always always do this, never trust ANYTHING completley). > > a) You may have one or two artifacts left over from the old install, but > you will be able to fix this fairly easily as each one is identified. > > b) Use the same user, it'll be fine. > > Remember, BACKUPS! > > -Matt Daubney > > regarding point B, if you create a new users then won't this cause permission issues, as say old system has /home/paul and the new install has /home/paul2 the files will still belong to paul, and will need to have ownership changed (chown) and (chgrp) so you can read as the new user. Just a thought, but this is something to perhaps consider, comments welcome in case I have perhaps mis understood something. I have my files on a different partition which makes sense, but you also make a good point regarding back ups. Paul - -- Paul Sutton www.zleap.net Support Open and ISO standard file formats ISO 26300 odf http://www.odfalliance.org Next Linux User Group meet :Saturday ** June 6th ** : 3pm, Shoreline Cafe Paignton -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkoT+bkACgkQaggq1k2FJq3UYQCcD6rGWCWsYd4O4YRsWC8vt/tP L9IAni3OEGAWAqAa97/UqLoae0ma50Od =Jkgf -END PGP SIGNATURE- -- ubuntu-uk@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-uk https://wiki.ubuntu.com/UKTeam/
