I'm trying to add a user with upper case letters:

[root@webserver4 bin]# useradd JasonTaylor
useradd: invalid user name 'JasonTaylor'

Anyone got ideas?

Thanks. I didn't have this problem in RedHat 8 or 7.3.

you could try the --force-badname option. that sometimes works with one of those commands (adduser or useradd), can't remember which.

>edit - it's the adduser command, info adduser:

[root@webserver4 bin]# useradd --force-badname JasonTaylor
useradd: invalid option -- -
usage: useradd [-u uid [-o]] [-g group] [-G group,...]
[-d home] [-s shell] [-c comment] [-m [-k template]]
[-f inactive] [-e expire ] [-p passwd] [-M] [-n] [-r] name
useradd -D [-g group] [-b base] [-s shell]
[-f inactive] [-e expire ]
[root@webserver4 bin]# adduser --force-badname JasonTaylor
adduser: invalid option -- -
usage: adduser [-u uid [-o]] [-g group] [-G group,...]
[-d home] [-s shell] [-c comment] [-m [-k template]]
[-f inactive] [-e expire ] [-p passwd] [-M] [-n] [-r] name
adduser -D [-g group] [-b base] [-s shell]
[-f inactive] [-e expire ]

Looks like no such love -- at least on Fedora.

n/m - didn't see adduser sandwiched in there.

fwiw, i got it to work once for me, then it wouldn't work anymore, either. it seems to be a squirrely command.

Yeah, was importing about 700 users from an old RH 8 box to the Fedora system. Tested a few accounts out to make sure they didn't screw up something with useradd. Since I'm migrating from RH 8 to Fedora, I wasn't sure when RH introduced this "feature". I ended up not fighting it and creating a new script to lowercase all the imported users and their repective home directories. I put a note on my website to tell all the users to login with all lowercase. I actually prefer that, but I had already allowed mixed case usernames. Really sux.

Thanks anyways.

I did a quick google search, but I can't find out why usernames have to begin with a lowercase letter.

Any links to sites that have the reasoning/history of this are much appreciated.

Seems silly -- if you like the command to automatically create the home directory, and other things, then you will have to remember to manually change anything after as needed. I can see why it might not like special characters, but why capitals?

I can't think why certain distros would deliberately limit useradd in that fashion.

So for now, I will (unfortunately) user all lowercase, and hopefully will remember when I login (I've gotten used to this name on Win-doze).

When I first installed Fedora, I merrily created myself a username starting with a capital V. Turns out that procmail - which sendmail uses by default in FC - can't handle uppercase letters without a special hack, which I never have figured out. Ever since, all internal system mail addressed to Vince bounces to root, with the procmail error: user Vince unknown. That's the only reason that I'm aware of for all-lowercase usernames.

Regards,
Vince

I suppose that's a good reason.

Is "sendmail" still maintained?

Yes, AFAIK. I've never been motivated enough to try an alternate MTA - my system mail is very low-volume - maybe Postfix (sic?) or others have no such problems. There may be other reasons to avoid uppercase letters in usernames that I'm not aware of - such as what the OP discovered.

I just used useradd to add a user JasonTaylor on my system. There was no apparent difficulty. I checked in the file /etc/passwd to make sure the capitals were preserved. I'm not aware of any rule against having user names with capital letters (except it's in poor taste).