[CentOS] E-mail advice sought

[Alice Wonder]

On 05/01/2016 01:57 AM, Leon Fauster wrote:
> Am 01.05.2016 um 06:43 schrieb Alice Wonder <alice at domblogger.net>:
>> On 04/30/2016 08:56 PM, Gordon Messmer wrote:
>>> On Sat, Apr 30, 2016 at 12:44 PM, Alice Wonder <alice at domblogger.net> wrote:
>>>>
>>>> For e-mail sent to people, yes.
>>>>
>>>> But for what usernames are allowed when creating an account, I don't see why
>>>> blacklisting characters that are not allowed in a username is a standards
>>>> problem.
>>>
>>>
>>> That's not how the RFC rules are defined.  But, rather than argue that
>>> point at length, I'd point out that Open Group standards for usernames
>>> are simple and will comply with the SMTP RFCs:
>>> http://pubs.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap03.html#tag_03_426
>>>
>>> That is, [A-Za-z0-9._][A-Za-z0-9._-]
>>> _______________________________________________
>>> CentOS mailing list
>>> CentOS at centos.org
>>> https://lists.centos.org/mailman/listinfo/centos
>>>
>>
>> I think there is a mis-understanding.
>>
>> All I was looking for was if there was a common set of characters typically blasted from new usernames *on the domain being set up*
>>
>> I have no desire to refuse delivery to any valid e-mail address.
>>
>> For example, avoiding spaces in usernames for addresses on the system is handy because it avoids bugs where the path to the mailbox on the filesystem isn't properly quoted.
>>
>> So user names on the system won't be allowed to have spaces even though they are legal when within quotes or escaped.
>>
>> That's all I was looking for, was experience on what legal characters to avoid allowing users to have for the mailbox portion of their e-mail address, the username.
>>
>> Of course I have no desire to restrict who they can send to if it is a legal address.
>
>
> blacklisting is not a good practice, use the suggested whitelist ...

I think this is my autism coming in to play, I think what is very clear 
to me I just am not able to adequately communicate because clearly 
people are not even remotely grasping what I am trying to convey.