User IDs
If the IBM® WebSphere® MQ MQI client is on Windows and the IBM WebSphere MQ server is also on Windows and has access to the domain on which the client user ID is defined, IBM WebSphere MQ supports user IDs of up to 20 characters. On UNIX and Linux® platforms and configurations, the maximum length is 12 characters.
A
WebSphere MQ for
Windows server
does not support the connection of a
Windows client
if the client is running under a user ID that contains the @ character,
for example, abc@d
. The return code to the MQCONN call
at the client is MQRC_NOT_AUTHORIZED.
However, you can specify the user ID using two @ characters, for
example, abc@@d
. Using the id@domain
format
is the preferred practice, to ensure that the user ID is resolved
in the correct domain consistently; thus abc@@d@domain
.
Note that UNKNOWN
is a reserved user ID and the NOBODY
user
ID also have special meanings to
WebSphere MQ.
Creating user IDs in the operating system called UNKNOWN
or NOBODY
could
have unintended results.
Although user IDs are used to authenticate, groups are used for authorization, except for Windows.
If you create service accounts, without paying attention to groups, and authorize all the user IDs differently, every user can access the information of every other user.