Below are the restrictions for the username and passwords.
From 5 to 32 characters allowed for username.
First character must be an "alpha" (A-Z, a-z).
Non-printables, <SPACE>, :, ;, ", @, *, \, /, ', `, <, >, &, |, . and , are not allowed.
From 8 to 32 characters allowed for password.
Non-printables, <SPACE>, are not allowed.
* Note the above restrictions also apply to the SNMP and Radius user/password settings.