Yes, there is, it's an AS400 thang.
You may also force a user to only be able to sign onto a session of a
certain name, but this will need a bit more research for you to do. But
fairly easy.
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Change User Profile (CHGUSRPRF)
Type choices, press Enter.
Additional Parameters
Special authority . . . . . . . *NONE *SAME, *USRCLS, *NONE...
+ for more values
Special environment . . . . . . *SYSVAL *SAME, *SYSVAL, *NONE, *S36
Display sign-on information . . *SYSVAL *SAME, *NO, *YES, *SYSVAL
Password expiration interval . . *SYSVAL 1-366, *SAME, *SYSVAL,
*NOMAX
Limit device sessions . . . . . *YES *SAME, *NO, *YES, *SYSVAL
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