I'm trying to figure out what characters the Cisco router doesn't like when creating a password or pre-shared key. Please help me understand this. Thank you.
Generally, the characters
[space] are the only il-advised characters. The
? indicates you are asking for help. The space indicates you are done with the password and moving onto the next command.
You should avoid
! since they could interfere with other commands as you type them.
username (user) password 0 ... everything to the end-of-line is the password - literally, even a "blind" trailing space! For an ASA,
username (user) password "..." everything inside the quotes is the password. (ctrlv will allow the input of
? on both platforms) (the use of quotes allows use of spaces, but then excludes the use quotes in the password)