On Fri, Dec 02, 2005 at 10:31:29AM +0000, T. Horsnell wrote: > 'morning all, > I see from my new RHEL4 sysadmin guide that uid's up to 500 are > reserved for system use. When I first began setting up my > Unix userbase some 15 years ago, I unfortunately chose to start > at uid 100, so I now have to change the uid's of some 400 users, > 36 million files, on a hundred or so boxes. OK, this is do-able > and should be more-or-less 'transparent to the user'. > (Since I'm going to make a change, should I start at 1000 and change > the lot? How reliable is the 500?) > The thing that concerns me more, is the plethora of reserved > usernames. There seems to be no rule to distinguish a reserved > username (presumably the list in the RHEL sysadmin guide is > going to grow) and its only a matter of time before some > newly allocated name collides with one which has been given to > a user. In fact, I cant find anywhere what the rules are for > usernames. Character-set? How many chars? > Pity that reserved names arent systematic in some way (like > always starting with sys_ or somesuch). > > I'm not looking forward to the day when a new system-username > duplicates the username of one of the directors, which he has > had for the last 15 years, and which is also his email address > held on mailing lists and institutions all over the place... > > Any advice out there? > > Cheers, > Terry. Well I have had a uid of 100 on our unix and Linux systems for years, There is generally no need to change uids below 500 except: lately fedora has increased the uids of their default system accounts, so sometimes you need to change their uids so that you can keep 100 for your own. But they can be changed to unused numbers between 1 and 99. There are several holes in the sequence of the system uids. That is simpler than changing 400 accounts. -- ======================================================================= Hanson's Treatment of Time: There are never enough hours in a day, but always too many days before Saturday. ------------------------------------------- Aaron Konstam Computer Science Trinity University telephone: (210)-999-7484
