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maximum number of logins with an expired password to three and the time period to 15 days, a user
can log in three times within 15 days after the password expires.
Password history
With this feature enabled, the system maintains certain entries of passwords that a user has used. When
a user changes the password, the system checks the new password against the used ones to see whether
it was used before and, if so, displays an error message.
set the maximum number of history password records for the system to maintain for each user. When the
number of history password records exceeds your setting, the latest record overwrites the earliest one.
Login attempt limit
Limiting the number of consecutive failed login attempts can effectively prevent password guessing.
If an FTP or VTY user fails authentication due to a password error, the system adds the user to a blacklist.
If a user fails to provide the correct password after the specified number of consecutive attempts, the
system takes configured actions as follows:
•
Prohibits the user from logging in until the user is removed from the blacklist manually.
•
Allows the user to try continuously and removes the user from the blacklist when the user logs in to
the system successfully or when the blacklist entry times out (the blacklist entry aging time is 1
minute).
•
Prohibits the user from logging in within a configurable period of time and allows the user to log in
again after the period of time elapses or after the user is removed from the blacklist.
NOTE:
•
A blacklist can contain up to 1024 entries.
•
A login attempt using a wrong username fails, but the username is not added into the blacklist.
•
Web users failing login authentication are not blacklisted. Users accessing the system through the
console or AUX interface are not blacklisted either. This is because the system is unable to obtain the
IP addresses of these users. These users are privileged and, therefore, relatively secure to the system.
Password composition checking
A password can be a combination of characters from the following categories:
•
Uppercase letters A to Z
•
Lowercase letters a to z
•
Digits 0 to 9
•
32 special characters including blank space and ~`!@#$%^&*()_+-={}|[]\:";'<>,./.
Depending on the system security requirements, set the minimum number of categories a password must
contain and the minimum number of characters of each category.
There are four password combination levels: 1, 2, 3, and 4, each representing the number of categories
that a password must at least contain. Level 1 means that a password must contain characters of one
category, level 2 at least two categories, and so on.
When a user sets or changes the password, the system checks if the password satisfies the composition
requirement. If not, the system displays an error message.
