Cisco Systems OL-8550-09 Protecting Enable and Enable Secret Passwords with Encryption

9-4
Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter9 Configuring Switch-Based Authenticatio n
Protecting Access to Privileged EXEC Commands
Protecting Enable and Enable Secret Passwords with Encryption
To provide an additional layer of security, particularly for passwords that cross the network or that are
stored on a Trivial File Transfer Protocol (TFTP) server, you can use either the enable password or
enable secret global configuration commands. Both commands accomplish the same thing; that is, you
can establish an encrypted password that users must enter to access privileged EXEC mode (the default)
or any privilege level you specify.
We recommend that you use the enable secret command because it uses an improved encryption
algorithm.
If you configure the enable secret command, it takes precedence over the enable password command;
the two commands cannot be in effect simultaneously.
Beginning in privileged EXEC mode, follow these steps to configure encryption for enable and enable
secret passwords:
Command Purpose
Step1 configure terminal Enter global configuration mode.
Step2 enable password [level level] {password |
encryption-type encrypted-password}
or
enable secret [level level] {password |
encryption-type encrypted-password}
Define a new password or change an existing password for
access to privileged EXEC mode.
or
Define a secret password, which is saved using a
nonreversible encryption method.
•(Optional) For level, the range is from 0 to 15. Level 1 is
normal user EXEC mode privileges. The default level is
15 (privileged EXEC mode privileges).
•For password, specify a string from 1 to 25
alphanumeric characters. The string cannot start with a
number, is case sensitive, and allows spaces but ignores
leading spaces. By default, no password is defined.
•(Optional) For encryption-type, only type 5, a Cisco
proprietary encryption algorithm, is available. If you
specify an encryption type, you must provide an
encrypted password—an encrypted password that you
copy from another switch configuration.
Note If you specify an encryption type and then enter a
clear text password, you can not re-enter privileged
EXEC mode. You cannot recover a lost encrypted
password by any method.
Step3 service password-encryption (Optional) Encrypt the password when the password is
defined or when the configuration is written.
Encryption prevents the password from being readable in the
configuration file.
Step4 end Return to privileged EXEC mode.
Step5 copy running-config startup-config (Optional) Save your entries in the configuration file.