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Cisco IOS Security Command Reference, Release 12.3 T
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Introduction
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Security Commands: aaa accounting through access-template
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Security Commands: accounting through clear ip ips statistics
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Security Commands: clear ip sdee through crypto isakmp nat keepalive
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Security Commands: crypto key decrypt rsa through ctype
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Security Commands: D through evaluate
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Security Commands: fingerprint through ip ips signature disable
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Security Commands: ip port-map through issuer name
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Security Commands: keepalive (isakmp profile) through outgoing
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Security Commands: parameter through quit
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Security Commands: radius-server attribute 11 direction default through rsa-pubkey
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Security Commands: save-password through show crypto ipsec transform-set
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Security Commands: show crypto isakmp key through subject-name
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Security Commands: tacacs-server administration through xauth userid mode
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Table Of Contents
parameter
To specify parameters for an enrollment profile, use the parameter command in ca-profile-enroll configuration mode. To disable specified parameters, use the no form of this command.
parameter number {value value | prompt string}
no parameter number {value value | prompt string}
Syntax Description
Defaults
No enrollment profile paramters are specified.
Command Modes
Ca-profile-enroll configuration
Command History
12.2(13)ZH
This command was introduced.
12.3(4)T
This command was integrated into Cisco IOS Release 12.3(4)T.
Usage Guidelines
The parameter command can be used within an enrollment profile after the authentication command command or the enrollment command has been enabled.
Examples
The following example shows how to specify parameters for the enrollment profile named "E":
crypto ca trustpoint Entrustenrollment profile Eserialcrypto ca profile enrollment Eauthentication url http://entrust:81authentication command GET /certs/cacert.derenrollment url http://entrust:81/cda-cgi/clientcgi.exeenrollment command POST reference_number=$P2&authcode=$P1&retrievedAs=rawDER&action=getServerCert&pkcs10Request=$REQparameter 1 value aaaa-bbbb-ccccparameter 2 value 5001Related Commands
parser view
To create or change a command-line interface (CLI) view and enter view configuration mode, use the parser view command in global configuration mode. To delete a view, use the no form of this command.
parser view view-name
no parser view view-name
Syntax Description
Defaults
A CLI view does not exist.
Command Modes
Global configuration
Command History
Usage Guidelines
A CLI view is a set of operational commands and configuration capabilities that restrict user access to the CLI and configuration information; that is, a view allows users to define what commands are accepted and what configuration information is visible.
After you have issued the parser view command, you can configure the view via the password 5 command and the commands command.
To use the parser view command, the system of the user must be set to root view. The root view can be enabled via the enable view command.
Examples
The following example show how to configure two CLI views, "first" and "second."
Router(config)# parser view first00:11:40:%PARSER-6-VIEW_CREATED:view 'first' successfully created.Router(config-view)# password 5 firstpassRouter(config-view)# command exec include show versionRouter(config-view)# command exec include configure terminalRouter(config-view)# command exec include all show ipRouter(config-view)# exitRouter(config)# parser view second00:13:42:%PARSER-6-VIEW_CREATED:view 'second' successfully created.Router(config-view)# password 5 secondpassRouter(config-view)# command exec include-exclusive show ip interfaceRouter(config-view)# command exec include logoutRouter(config-view)# exitAfter you have successfully created a view, a system message such as the following will be displayed:
%PARSER-6-VIEW_CREATED: view `first' successfully created.After you have successfully deleted a view, a system message such as the following will be displayed:
%PARSER-6-VIEW_DELETED: view `first' successfully deleted.Related Commands
commands (view)
Adds commands to a CLI view.
password 5
Associates a CLI view or a superview with a password.
parser view superview
To create a superview and enter view configuration mode, use the parser view superview command in global configuration mode. To delete a superview, use the no form of this command.
parser view superview-name superview
no parser view superview-name superview
Syntax Description
superview-name
Superview name, which can include 1 to 30 alphanumeric characters.
The superview-name argument must not have a number as the first character.
Defaults
A superview does not exist.
Command Modes
Global configuration
Command History
Usage Guidelines
A superview consists of one or more command-line interface (CLI) views, which allow users to define what commands are accepted and what configuration information is visible. Superviews allow a network administrator to easily assign all users within configured CLI views to a superview instead of having to assign multiple CLI views to a group of users.
Superviews contain the following characteristics:
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A CLI view can be shared among multiple superviews.
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Adding CLI Views to a Superview
You can add a view to a superview only after a password has been configured for the superview (via the password 5 command). Thereafter, issue the view command in view configuration mode to add at least one CLI view to the superview.
Note
Examples
The following sample output from the show running-config command shows that "view_one" and "view_two" have been added to superview "su_view1," and "view_three" and "view_four" have been added to superview "su_view2":
!parser view su_view1 superviewpassword5 <encoded password>view view_oneview view_two!parser view su_view2 superviewpassword5 <encoded password>view view_threeview view_four!Related Commands
password (ca-trustpoint)
To specify the revocation password for the certificate, use the password command in ca-trustpoint configuration mode. To erase any stored passwords, use the no form of this command.
password string
no password
Syntax Description
Defaults
You are prompted for the password during certificate enrollment.
Command Modes
Ca-trustpoint configuration
Command History
Usage Guidelines
Before you can issue the password command, you must enable the crypto ca trustpoint command, which declares the certification authority (CA) that your router should use and enters ca-trustpoint configuration mode.
This command allows you to specify the revocation password for the certificate before actual certificate enrollment begins. The specified password is encrypted when the updated configuration is written to NVRAM by the router.
If this command is enabled, you will not be prompted for a password during certificate enrollment.
Examples
The following example shows how to specify the password "revokme" for the certificate request:
crypto ca trustpoint frogenrollment url http://frog.phoobin.com/subject-name OU=Spiral Dept., O=tiedye.comip-address ethernet-0auto-enroll regeneratepassword revokmeRelated Commands
password (line configuration)
To specify a password on a line, use the password command in line configuration mode. To remove the password, use the no form of this command.
password password
no password
Syntax Description
Defaults
No password is specified.
Command Modes
Line configuration
Command History
Usage Guidelines
When an EXEC process is started on a line with password protection, the EXEC prompts for the password. If the user enters the correct password, the EXEC prints its normal privileged prompt. The user can try three times to enter a password before the EXEC exits and returns the terminal to the idle state.
Examples
The following example removes the password from virtual terminal lines 1 to 4:
line vty 1 4 no passwordRelated Commands
enable password
Sets a local password to control access to various privilege levels.
password 5
Note
To associate a command-line interface (CLI) view or a superview with a password, use the password 5 command in view configuration mode.
password 5 password
Syntax Description
password
Password for users to enter the CLI view or superview. A password can contain any combination of alphanumeric characters.
Note
Defaults
A user cannot access a CLI view or superview.
Command Modes
View configuration
Command History
12.3(7)T
This command was introduced.
12.3(11)T
This command was enhanced to support superviews.
12.3(14)T
This command was replaced by the secret command.
Usage Guidelines
A user cannot access any commands within the CLI view or superview until the password 5 command has been issued.
Examples
The following example show how to configure two CLI views, "first" and "second" and associate each view with a password:
Router(config)# parser view first00:11:40:%PARSER-6-VIEW_CREATED:view 'first' successfully created.Router(config-view)# password 5 firstpassRouter(config-view)# command exec include show versionRouter(config-view)# command exec include configure terminalRouter(config-view)# command exec include all show ipRouter(config-view)# exitRouter(config)# parser view second00:13:42:%PARSER-6-VIEW_CREATED:view 'second' successfully created.Router(config-view)# password 5 secondpassRouter(config-view)# command exec include-exclusive show ip interfaceRouter(config-view)# command exec include logoutRouter(config-view)# exitRelated Commands
password encryption aes
To enable a type 6 encrypted preshared key, use the password encryption aes command in global configuration mode. To disable password encryption, use the no form of this command.
password encryption aes
no password encryption aes
Syntax Description
This command has no arguments or keywords.
Defaults
Preshared keys are not encrypted.
Command Modes
Global configuration
Command History
Usage Guidelines
You can securely store plain text passwords in type 6 format in NVRAM using a command-line interface (CLI). Type 6 passwords are encrypted. Although the encrypted passwords can be seen or retrieved, it is difficult to decrypt them to find out the actual password. Use the key config-key password-encryption command with the password encryption aes command to configure and enable the password (symmetric cipher Advanced Encryption Standard [AES] is used to encrypt the keys). The password (key) configured using the key config-key password-encryption command is the master encryption key that is used to encrypt all other keys in the router.
If you configure the password encryption aes command without configuring the key config-key password-encryption command, the following message is printed at startup or during any nonvolatile generation (NVGEN) process, such as when the show running-config or copy running-config startup-config commands have been configured:
"Can not encrypt password. Please configure a configuration-key with `key config-key'"
Note
Changing a Password
If the password (master key) is changed, or reencrypted, using the key config-key password-encryption command), the list registry passes the old key and the new key to the application modules that are using type 6 encryption.
Deleting a Password
If the master key that was configured using the key config-key password-encryption command is deleted from the system, a warning is printed (and a confirm prompt is issued) that states that all type 6 passwords will become useless. As a security measure, after the passwords have been encrypted, they will never be decrypted in the Cisco IOS software. However, passwords can be reencrypted as explained in the previous paragraph.
Caution
Unconfiguring Password Encryption
If you later unconfigure password encryption using the no password encryption aes command, all existing type 6 passwords are left unchanged, and as long as the password (master key) that was configured using the key config-key password-encryption command exists, the type 6 passwords will be decrypted as and when required by the application.
Storing Passwords
Because no one can "read" the password (configured using the key config-key password-encryption command), there is no way that the password can be retrieved from the router. Existing management stations cannot "know" what it is unless the stations are enhanced to include this key somewhere, in which case the password needs to be stored securely within the management system. If configurations are stored using TFTP, the configurations are not standalone, meaning that they cannot be loaded onto a router. Before or after the configurations are loaded onto a router, the password must be manually added (using the key config-key password-encryption command). The password can be manually added to the stored configuration but is not recommended because adding the password manually allows anyone to decrypt all passwords in that configuration.
Configuring New or Unknown Passwords
If you enter or cut and paste cipher text that does not match the master key, or if there is no master key, the cipher text is accepted or saved, but an alert message is printed. The alert message is as follows:
"ciphertext>[for username bar>] is incompatible with the configured master key."If a new master key is configured, all the plain keys are encrypted and made type 6 keys. The existing type 6 keys are not encrypted. The existing type 6 keys are left as is.
If the old master key is lost or unknown, you have the option of deleting the master key using the no key config-key password-encryption command. Deleting the master key using the no key config-key password-encryption command causes the existing encrypted passwords to remain encrypted in the router configuration. The passwords will not be decrypted.
Examples
The following example shows that a type 6 encrypted preshared key has been enabled:
Router (config)# password encryption aesRelated Commands
key config-key password-encryption
Stores a type 6 encryption key in private NVRAM.
password logging
Provides a log of debugging output for a type 6 password operation.
password logging
To get a log of debugging output for a type 6 password operation, use the password logging command in privileged EXEC mode. To disable the debugging, use the no form of this command.
password logging
no password logging
Syntax Description
This command has no arguments or keywords.
Defaults
Debug logging is not enabled.
Command Modes
Privileged EXEC
Command History
Examples
The following example shows that debug logging is configured:
Router# password loggingRelated Commands
key config-key password-encryption
Stores an encryption key in private NVRAM.
password encryption aes
Enables a type 6 encrypted preshared key.
permit (reflexive)
To create a reflexive access list and to enable its temporary entries to be automatically generated, use the permit command in access-list configuration mode. To delete the reflexive access list (if only one protocol was defined) or to delete protocol entries from the reflexive access list (if multiple protocols are defined), use the no form of this command.
permit protocol source source-wildcard destination destination-wildcard reflect name [timeout seconds]
no permit protocol source-wildcard destination destination-wildcard reflect name
Syntax Description
Defaults
If this command is not configured, no reflexive access lists will exist, and no session filtering will occur.
If this command is configured without specifying a timeout value, entries in this reflexive access list will expire after the global timeout period.
Command Modes
Access-list configuration
Command History
Usage Guidelines
This command is used to achieve reflexive filtering, a form of session filtering.
For this command to work, you must also nest the reflexive access list using the evaluate command.
This command creates a reflexive access list and triggers the creation of entries in the same reflexive access list. This command must be an entry (condition statement) in an extended named IP access list.
If you are configuring reflexive access lists for an external interface, the extended named IP access list should be one which is applied to outbound traffic.
If you are configuring reflexive access lists for an internal interface, the extended named IP access list should be one which is applied to inbound traffic.
IP sessions that originate from within your network are initiated with a packet exiting your network. When such a packet is evaluated against the statements in the extended named IP access list, the packet is also evaluated against this reflexive permit entry.
As with all access list entries, the order of entries is important, because they are evaluated in sequential order. When an IP packet reaches the interface, it will be evaluated sequentially by each entry in the access list until a match occurs.
If the packet matches an entry prior to the reflexive permit entry, the packet will not be evaluated by the reflexive permit entry, and no temporary entry will be created for the reflexive access list (session filtering will not be triggered).
The packet will be evaluated by the reflexive permit entry if no other match occurs first. Then, if the packet matches the protocol specified in the reflexive permit entry, the packet is forwarded and a corresponding temporary entry is created in the reflexive access list (unless the corresponding entry already exists, indicating the packet belongs to a session in progress). The temporary entry specifies criteria that permits traffic into your network only for the same session.
Characteristics of Reflexive Access List Entries
This command enables the creation of temporary entries in the same reflexive access list that was defined by this command. The temporary entries are created when a packet exiting your network matches the protocol specified in this command. (The packet "triggers" the creation of a temporary entry.) These entries have the following characteristics:
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If the original triggering packet is a protocol other than TCP or UDP, port numbers do not apply, and other criteria are specified. For example, for ICMP, type numbers are used: the temporary entry specifies the same type number as the original packet (with only one exception: if the original ICMP packet is type 8, the returning ICMP packet must be type 0 to be matched).
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Examples
The following example defines a reflexive access list tcptraffic, in an outbound access list that permits all Border Gateway Protocol and Enhanced Interior Gateway Routing Protocol traffic and denies all ICMP traffic. This example is for an external interface (an interface connecting to an external network).
First, the interface is defined and the access list is applied to the interface for outbound traffic.
interface Serial 1description Access to the Internet via this interfaceip access-group outboundfilters outNext, the outbound access list is defined and the reflexive access list tcptraffic is created with a reflexive permit entry.
ip access-list extended outboundfilterspermit tcp any any reflect tcptrafficRelated Commands
pfs
To configure a server to notify the client of the central-site policy regarding whether PFS is required for any IP Security (IPSec) Security Association (SA), use the pfs command in global configuration mode. To restore the default behavior, use the no form of this command.
pfs
no pfs
Syntax Description
This command has no arguments or keywords.
Defaults
The server will not notify the client of the central-site policy regarding whether PFS is required for any IPSec SA.
Command Modes
Global configuration
Command History
Usage Guidelines
Before you use the pfs command, you must first configure the crypto isakmp client configuration group command.
An example of an attribute-value (AV) pair for the PFS attribute is as follows:
ipsec:pfs=1Examples
The following example shows that the server has been configured to notify the client of the central-site policy regarding whether PFS is required for any IPSec SA:
crypto isakmp client configuration grouppfsRelated Commands
crypto isakmp client configuration group
Specifies to which group a policy profile will be defined.
pki-server
To specify the certificate server that is to be associated with the Trusted Transitive Introduction (TTI) exchange between the easy secure device deployment (EzSDD) petitioner and the EzSDD registrar, use the pki-server command in tti-registrar configuration mode. To change the specified certificate server, use the no form of this command.
pki-server label
no pki-server label
Syntax Description
Defaults
A certificate server is not associated with the TTI exchange; thus, the petitioner and registrar will not be able to communicate.
Command Modes
tti-registrar configuration
Command History
Usage Guidelines
Although any device that contains a crypto image can be the registrar, it is recommended that the registrar be either a Cisco IOS certificate server registration authority (RA) or a Cisco IOS certificate server root.
Examples
The following example shows how to associate the certificate server "cs1" with the TTI exchange:
crypto wui tti registrarpki-server cs1Related Commands
pool (isakmp-group)
To define a local pool address, use the pool command in Internet Security Association Key Management Protocol (ISAKMP) group configuration mode. To remove a local pool from your configuration, use the no form of this command.
pool name
no pool name
Syntax Description
Defaults
No default behavior or values.
Command Modes
ISAKMP group configuration
Command History
Usage Guidelines
Use the pool command to refer to an IP local pool address, which defines a range of addresses that will be used to allocate an internal IP address to a client. Although a user must define at least one pool name, a separate pool may be defined for each group policy.
Note
You must enable the crypto isakmp client configuration group command, which specifies group policy information that has to be defined or changed, before enabling the pool command.
Examples
The following example shows how to refer to the local pool address "dog":
crypto isakmp client configuration group ciscokey ciscodns 10.2.2.2 10.3.2.3pool dogacl 199!ip local pool dog 10.1.1.1 10.1.1.254Related Commands
port-forward
To list the set of forwarded ports to which a user has access, use the port-forward command in Web VPN configuration mode. To remove ports, use the no form of this command.
port-forward {list list-name} {local-port port-number} {remote-server server-name-or-IP-address} {remote-port port-number}
no port-forward {list list-name} {local-port port-number} {remote-server server-name-or-IP-address} {remote-port port-number}
Syntax Description
Defaults
No default behavior or values.
Command Modes
Web VPN configuration
Command History
Usage Guidelines
This command is used for TCP port forwarding.
Examples
The following example shows that the list name is POP3, the local port is 60002, the remote server is mail.youremail.com, and the remote port number is 25:
Router (config)# webvpnRouter (config-webvpn)# port-forward list POP3 local-port 60002 remote-server mail.youremail.com remote-port 25Related CommandsRout
port-misuse
To permit or deny HTTP traffic through the firewall on the basis of specified applications in the HTTP message, use the port-misuse command in appfw-policy-http configuration mode. To disable this inspection parameter, use the no form of this command.
port-misuse {p2p | tunneling | im | default} action {reset | allow} [alarm]
no port-misuse {p2p | tunneling | im | default} action {reset | allow} [alarm]
Syntax Description
Defaults
If this command is not enabled, HTTP messages are permitted through the firewall if any of the applications are detected within the message.
Command Modes
appfw-policy-http configuration
Command History
Examples
The following example shows how to define the HTTP application firewall policy "mypolicy." This policy includes all supported HTTP policy rules. After the policy is defined, it is applied to the inspection rule "firewall," which will inspect all HTTP traffic entering the FastEthernet0/0 interface.
! Define the HTTP policy.appfw policy-name mypolicyapplication httpstrict-http action allow alarmcontent-length maximum 1 action allow alarmcontent-type-verification match-req-rsp action allow alarmmax-header-length request 1 response 1 action allow alarmmax-uri-length 1 action allow alarmport-misuse default action allow alarmrequest-method rfc default action allow alarmrequest-method extension default action allow alarmtransfer-encoding type default action allow alarm!!! Apply the policy to an inspection rule.ip inspect name firewall appfw mypolicyip inspect name firewall http!!! Apply the inspection rule to all HTTP traffic entering the FastEthernet0/0 interface.interface FastEthernet0/0ip inspect firewall in!!ppp accounting
To enable authentication, authorization, and accounting (AAA) accounting services on the selected interface, use the ppp accounting command in interface configuration mode. To disable AAA accounting services, use the no form of this command.
ppp accounting default
no ppp accounting
Syntax Description
Defaults
Accounting is disabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
After you enable the aaa accounting command and define a named accounting method list (or use the default method list), you must apply the defined lists to the appropriate interfaces for accounting services to take place. Use the ppp accounting command to apply the specified method lists (or if none is specified, the default method list) to the selected interface.
Examples
The following example enables accounting on asynchronous interface 4 and uses the accounting method list named charlie:
interface async 4encapsulation pppppp accounting charlieRelated Commands
aaa accounting
Enables AAA accounting of requested services for billing or security purposes.
ppp authentication
To enable at least one PPP authentication protocol and to specify the order in which the protocols are selected on the interface, use the ppp authentication command in interface configuration mode. To disable this authentication, use the no form of this command.
ppp authentication {protocol1 [protocol2...]} [if-needed] [list-name | default] [callin] [one-time] [optional]
no ppp authentication
Syntax Description
protocol1 [protocol2...]
At least one of the keywords described in Table 29.
if-needed
(Optional) Used with TACACS and extended TACACS. Does not perform Challenge Handshake Authentication Protocol (CHAP) or Password Authentication Protocol (PAP) authentication if authentication has already been provided. This option is available only on asynchronous interfaces.
list-name
(Optional) Used with authentication, authorization, and accounting (AAA). Specifies the name of a list of methods of authentication to use. If no list name is specified, the system uses the default. The list is created with the aaa authentication ppp command.
default
(Optional) Name of the method list created with the aaa authentication ppp command.
callin
(Optional) Authentication on incoming (received) calls only.
one-time
(Optional) The username and password are accepted in the username field.
optional
(Optional) Accepts the connection even if the peer refuses to accept the authentication methods that the router has requested.
Defaults
PPP authentication is not enabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
When you enable PAP, CHAP, or Extensible Authentication Protocol (EAP) authentication (or all three methods), the local router requires the remote device to prove its identity before allowing data traffic to flow. PAP authentication requires the remote device to send a name and a password, which is checked against a matching entry in the local username database or in the remote security server database. CHAP authentication sends a challenge message to the remote device. The remote device encrypts the challenge value with a shared secret and returns the encrypted value and its name to the local router in a Response message. The local router attempts to match the name of the remote device with an associated secret stored in the local username or remote security server database; it uses the stored secret to encrypt the original challenge and verify that the encrypted values match. EAP works much as CHAP does, except that identity request and response packets are exchanged when EAP starts.
You can enable CHAP, Microsoft CHAP (MS-CHAP), PAP, or EAP in any order. If you enable all four methods, the first method specified is requested during link negotiation. If the peer suggests using the second method, or refuses the first method, the second method is tried. Some remote devices support only one method. Base the order in which you specify methods on the ability of the remote device to correctly negotiate the appropriate method and on the level of data-line security you require. PAP usernames and passwords are sent as clear text strings, which can be intercepted and reused.
Caution
Table 29 lists the protocols used to negotiate PPP authentication.
Enabling or disabling PPP authentication does not affect the ability of the local router to authenticate itself to the remote device.
If you are using autoselect on a tty line, you can use the ppp authentication command to turn on PPP authentication for the corresponding interface.
MS-CHAP is the Microsoft version of CHAP. Like the standard version of CHAP, MS-CHAP is used for PPP authentication; authentication occurs between a personal computer using Microsoft Windows NT or Microsoft Windows 95 and a Cisco router or access server acting as a network access server.
To configure Cisco PDSN in compliance with the TIA/EIA/IS-835-B standard, you must configure the PDSN virtual template as follows:
ppp authentication chap pap optionalExamples
The following example configures virtual-template interface 4:
interface virtual-template 4ip unnumbered loopback0ppp authentication chap pap optionalThe following example enables CHAP on asynchronous interface 4 and uses the authentication list MIS-access:
interface async 4encapsulation pppppp authentication chap MIS-accessThe following example enables EAP on dialer interface 1:
interface dialer 1encapsulation pppppp authentication eapRelated Commands
ppp authentication ms-chap-v2
To enable Microsoft Challenge Handshake Authentication Protocol Version 2 (MSCHAP V2) authentication on a network access server (NAS), use the ppp authentication ms-chap-v2 command in interface configuration mode. To disable MSCHAP V2 authentication, use the no form of this command.
ppp authentication ms-chap-v2
no ppp authentication ms-chap-v2
Syntax Description
This command has no arguments or keywords.
Defaults
MSCHAP V2 authentication is disabled.
Command Modes
Interface configuration
Command History
12.2(2)XB5
This command was introduced.
12.2(13)T
This command was integrated into Cisco IOS Release 12.2(13)T.
Usage Guidelines
To enable MSCHAP V2 authentication, first configure PPP on the NAS. For the NAS to properly interpret authentication failure attributes and vendor-specific attributes, the ppp max-bad-auth command must be configured to allow at least two authentication retries and the radius-server vsa send command and authentication keyword must be enabled. The NAS must be able to interpret authentication failure attributes and vendor-specific attributes to support the ability to change an expired password.
Examples
The following example configures PPP on an asynchronous interface and enables MSCHAP V2 authentication locally:
interface Async65ip address 10.0.0.2 255.0.0.0encapsulation pppasync mode dedicatedno peer default ip addressppp max-bad-auth 3ppp authentication ms-chap-v2username client password secretThe following example configures PPP on an asynchronous interface and enables MSCHAP V2 authentication via RADIUS:
interface Async65ip address 10.0.0.2 255.0.0.0encapsulation pppasync mode dedicatedno peer default ip addressppp max-bad-auth 3ppp authentication ms-chap-v2exitaaa authentication ppp default group radiusradius-server host 10.0.0.2 255.0.0.0radius-server key secretradius-server vsa send authenticationRelated Commands
ppp authorization
To enable authentication, authorization, and accounting (AAA) authorization on the selected interface, use the ppp authorization command in interface configuration mode. To disable authorization, use the no form of this command.
ppp authorization [default | list-name]
no ppp authorization
Syntax Description
Defaults
Authorization is disabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
After you enable the aaa authorization command and define a named authorization method list (or use the default method list), you must apply the defined lists to the appropriate interfaces for authorization to take place. Use the ppp authorization command to apply the specified method lists (or if none is specified, the default method list) to the selected interface.
Examples
The following example enables authorization on asynchronous interface 4 and uses the method list named charlie:
interface async 4encapsulation pppppp authorization charlieRelated Commands
ppp chap hostname
To create a pool of dialup routers that all appear to be the same host when authenticating with Challenge Handshake Authentication Protocol (CHAP), use the ppp chap hostname command in interface configuration mode. To disable this function, use the no form of this command.
ppp chap hostname hostname
no ppp chap hostname hostname
Syntax Description
Defaults
Disabled. The router name is sent in any CHAP challenges.
Command Modes
Interface configuration
Command History
Usage Guidelines
The ppp chap hostname command allows you to specify a common alias for all routers in a rotary group to use so that only one username must be configured on the dialing routers.
This command is normally used with local CHAP authentication (when the router authenticates to the peer), but it can also be used for remote CHAP authentication.
Examples
The following example identifies dialer interface 0 as the dialer rotary group leader and specifies "ppp" as the encapsulation method used by all member interfaces. This example shows that CHAP authentication is used on received calls only and the username ISPCorp will be sent in all CHAP challenges and responses.
interface dialer 0encapsulation pppppp authentication chap callinppp chap hostname ISPCorpRelated Commands
ppp chap password
To enable a router calling a collection of routers that do not support this command (such as routers running older Cisco IOS software images) to configure a common Challenge Handshake Authentication Protocol (CHAP) secret password to use in response to challenges from an unknown peer, use the ppp chap password command in interface configuration mode. To disable the PPP CHAP password, use the no form of this command.
ppp chap password secret
no ppp chap password secret
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
This command allows you to replace several username and password configuration commands with a single copy of this command on any dialer interface or asynchronous group interface.
This command is used for remote CHAP authentication only (when routers authenticate to the peer) and does not affect local CHAP authentication.
Examples
The commands in the following example specify ISDN BRI number 0. The method of encapsulation on the interface is PPP. If a CHAP challenge is received from a peer whose name is not found in the global list of usernames, the encrypted secret 7 1267234591 is decrypted and used to create a CHAP response value.
interface bri 0encapsulation pppppp chap password 7 1234567891Related Commands
ppp chap refuse
To refuse Challenge Handshake Authentication Protocol (CHAP) authentication from peers requesting it, use the ppp chap refuse command in interface configuration mode. To allow CHAP authentication, use the no form of this command.
ppp chap refuse [callin]
no ppp chap refuse [callin]
Syntax Description
Defaults
Disabled
Command Modes
Interface configuration
Command History
Usage Guidelines
This command specifies that CHAP authentication is disabled for all calls, meaning that all attempts by the peer to force the user to authenticate using CHAP will be refused. If the callin keyword is used, CHAP authentication is disabled for incoming calls from the peer, but will still be performed on outgoing calls to the peer.
If outbound Password Authentication Protocol (PAP) has been enabled (using the ppp pap sent-username command), PAP will be suggested as the authentication method in the refusal packet.
Examples
The following example specifies ISDN BRI number 0. The method of encapsulation on the interface is PPP. This example disables CHAP authentication from occurring if a peer calls in requesting CHAP authentication.
interface bri 0encapsulation pppppp chap refuseRelated Commands
ppp chap wait
To specify that the router will not authenticate to a peer requesting Challenge Handshake Authentication Protocol (CHAP) authentication until after the peer has authenticated itself to the router, use the ppp chap wait command in interface configuration mode. To allow the router to respond immediately to an authentication challenge, use the no form of this command.
ppp chap wait secret
no ppp chap wait secret
Syntax Description
Defaults
Enabled
Command Modes
Interface configuration
Command History
Usage Guidelines
This command (which is enabled by default) specifies that the router will not authenticate to a peer requesting CHAP authentication until the peer has authenticated itself to the router. The no form of this command specifies that the router will respond immediately to an authentication challenge.
Examples
The following example specifies ISDN BRI number 0. The method of encapsulation on the interface is PPP. This example disables the default, meaning that users do not have to wait for peers to complete CHAP authentication before authenticating themselves.
interface bri 0encapsulation pppno ppp chap waitRelated Commands
ppp eap identity
To specify the Extensible Authentication Protocol (EAP) identity, use the ppp eap identity command in interface configuration mode. To remove the EAP identity from your configuration, use the no form of this command.
ppp eap identity string
no ppp eap identity string
Syntax Description
Defaults
No default behavior or values
Command Modes
Interface configuration
Command History
12.2(2)XB5
This command was introduced.
12.2(13)T
This command was integrated into Cisco IOS Release 12.2(13)T.
Usage Guidelines
Use the ppp eap identity command to configure the client to use a different identity when requested by the peer.
Examples
The following example shows how to enable EAP on dialer interface 1 and set the identity to "cat":
interface dialer 1encapsulation pppppp eap identity catppp eap local
To authenticate locally instead of using the RADIUS back-end server, use the ppp eap local command in interface configuration mode. To reenable proxy mode (which is the default), use the no form of this command.
ppp eap local
no ppp eap local
Syntax Description
This command has no arguments or keywords.
Defaults
Authentication is performed via proxy mode.
Command Modes
Interface configuration
Command History
12.2(2)XB5
This command was introduced.
12.2(13)T
This command was integrated into Cisco IOS Release 12.2(13)T.
Usage Guidelines
By default, Extensible Authentication Protocol (EAP) runs in proxy mode. This means that EAP allows the entire authentication process to be negotiated by the network access server (NAS) to a back-end server that may reside on or be accessed via a RADIUS server. To disable proxy mode (and thus to authenticate locally instead of via RADIUS), use the ppp eap local command.
In local mode, the EAP session is authenticated using the MD5 algorithm and obeys the same authentication rules as does Challenge Handshake Authentication Protocol (CHAP).
Examples
The following example shows how to configure EAP to authenticate locally:
interface dialer 1encapsulation pppppp authentication eapppp eap localRelated Commands
ppp authentication
Enables at least one PPP authentication protocol and specifies the order in which the protocols are selected on the interface.
ppp eap password
To set the Enhanced Authentication Protocol (EAP) password for peer authentication, use the ppp eap password command in interface configuration mode. To disable the password, use the no form of this command.
ppp eap password [number] string
no ppp eap password [number] string
Syntax Description
number
(Optional) Encryption type, including values 0 through 7; 0 means no encryption.
string
Character string that specifies the EAP password.
Defaults
No default behavior or values
Command Modes
Interface configuration
Command History
12.2(2)XB5
This command was introduced.
12.2(13)T
This command was integrated into Cisco IOS Release 12.2(13)T.
Usage Guidelines
For remote EAP authentication only, you can configure your router to create a common EAP password to use in response to challenges from an unknown peer; for example, if your router calls a rotary of routers (either from another vendor or from an older running version of the Cisco IOS software) to which a new (that is, unknown) router has been added, the common password will be used to respond to the new router. The ppp eap password command allows you to replace several username and password configuration commands with a single copy of this command on any dialer interface or asynchronous group interface.
Examples
The following example shows how to set the EAP password "7 141B1309" on the client:
ppp eap identity userppp eap password 7 141B1309ppp eap refuse
To refuse Enhanced Authentication Protocol (EAP) from peers requesting it, use the ppp eap refuse command in interface configuration mode. To return to the default, use the no form of this command.
ppp eap refuse [callin]
no ppp eap refuse [callin]
Syntax Description
Defaults
The server will not refuse EAP authentication challenges received from the peer.
Command Modes
Interface configuration
Command History
12.2(2)XB5
This command was introduced.
12.2(13)T
This command was integrated into Cisco IOS Release 12.2(13)T.
Usage Guidelines
Use the ppp eap refuse command to disable EAP authentication for all calls. If the callin keyword is used, the server will refuse to answer EAP authentication challenges received from the peer but will still require the peer to answer any EAP challenges the server sends.
Examples
The following example shows how to refuse EAP authentication on incoming calls from the peer:
ppp authentication eapppp eap localppp eap refuse callinRelated Commands
ppp authentication
Enables at least one PPP authentication protocol and specifies the order in which the protocols are selected on the interface.
ppp eap wait
To configure the server to delay the Enhanced Authentication Protocol (EAP) authentication until after the peer has authenticated itself to the server, use the ppp eap wait command in interface configuration mode. To disable this functionality, use the no form of this command.
ppp eap wait
no ppp eap wait
Syntax Description
This command has no arguments or keywords.
Defaults
No default behavior or values
Command Modes
Interface configuration
Command History
12.2(2)XB5
This command was introduced.
12.2(13)T
This command was integrated into Cisco IOS Release 12.2(13)T.
Usage Guidelines
Use the ppp eap wait command to specify that the server will not authenticate to a peer requesting EAP authentication until after the peer has authenticated itself to the server.
Examples
The following example shows how to configure the server to wait for the peer to authenticate itself first:
ppp authentication eapppp eap localppp eap waitRelated Commands
ppp authentication
Enables at least one PPP authentication protocol and specifies the order in which the protocols are selected on the interface.
ppp pap refuse
To refuse a peer request to authenticate remotely with PPP using Password Authentication Protocol (PAP), use the ppp pap refuse command in interface configuration mode. To disable the refusal, use the no form of this command.
ppp pap refuse
no ppp pap refuse
Syntax Description
This command has no arguments or keywords.
Defaults
No default behavior or values.
Command Modes
Interface configuration
Command History
Usage Guidelines
Use this command to refuse remote PAP support; for example, to respond to the peer request to authenticate with PAP.
This is a per-interface command.
Examples
The following example shows how to enable the ppp pap command to refuse a peer request for remote authentication:
interface dialer 0encapsulation pppppp pap refuseRelated Commands
ppp pap sent-username
To reenable remote Password Authentication Protocol (PAP) support for an interface and use the sent-username and password in the PAP authentication request packet to the peer, use the ppp pap sent-username command in interface configuration mode. To disable remote PAP support, use the no form of this command.
ppp pap sent-username username password password
no ppp pap sent-username
Syntax Description
username
Username sent in the PAP authentication request.
password
Password sent in the PAP authentication request.
password
Must contain from 1 to 25 uppercase and lowercase alphanumeric characters.
Defaults
Remote PAP support disabled.
Command Modes
Interface configuration
Command History
Usage Guidelines
Use this command to reenable remote PAP support (for example, to respond to the peer's request to authenticate with PAP) and to specify the parameters to be used when sending the PAP authentication request.
This is a per-interface command. You must configure this command for each interface.
Examples
The following example identifies dialer interface 0 as the dialer rotary group leader and specify PPP as the method of encapsulation used by the interface. Authentication is by CHAP or PAP on received calls only. ISPCorp is the username sent to the peer if the peer requires the router to authenticate with PAP.
interface dialer0encapsulation pppppp authentication chap pap callinppp chap hostname ISPCorpppp pap sent username ISPCorp password 7 fjhfeuRelated Commands
pre-shared-key
To define a preshared key to be used for Internet Key Exchange (IKE) authentication, use the pre-shared-key command in keyring configuration mode. To disable the preshared key, use the no form of this command.
pre-shared-key {address address [mask] | hostname hostname} key key
no pre-shared-key {address address [mask] | hostname hostname} key key
Syntax Description
Defaults
No default behaviors or values
Command Modes
Keyring configuration
Command History
Usage Guidelines
Before configuring preshared keys, you must configure an Internet Security Association and Key Management Protocol (ISAKMP) profile.
Output for the pre-shared-key command will show that the preshared key is either unencrypted or encrypted. An output example for an unencrypted preshared key would be as follows:
pre-shared-key address 10.1.0.1 key test123An output example for a type 6 encrypted preshared key would be as follows:
pre-shared-key address 10.1.0.1 key 6 RHZE[JACMUI\bcbTdELISAAB
Examples
The following example shows how to configure a preshared key using an IP address and host name:
Router (config)# crypto keyring vpnkeyringRouter (config-keyring)# pre-shared-key address 10.72.23.11 key vpnkeyRouter (config-keyring)# pre-shared-key hostname www.vpn.com key vpnkeyprimary
To assign a specified trustpoint as the primary trustpoint of the router, use the primary command in ca-trustpoint configuration mode.
primary name
Syntax Description
Defaults
No default behavior or values.
Command Modes
Ca-trustpoint configuration
Command History
Usage Guidelines
Use the primary command to specify a given trustpoint as primary.
Before you can configure this command, you must enable the crypto ca trustpoint command, which defines the trustpoint and enters ca-trustpoint configuration mode.
Examples
The following example shows how to configure the trustpoint "ka" as the primary trustpoint:
crypto ca trustpoint kaenrollment url http://xxxprimarycrl optionalRelated Commands
privilege
To configure a new privilege level for users and associate commands with that privilege level, use the privilege command in global configuration mode. To reset the privilege level of the specified command or commands to the default and remove the privilege level configuration from the running configuration file, use the no form of this command.
Note
privilege mode [all] {level level | reset} command-string
no privilege mode [all] {level level | reset} command-string
Syntax Description
mode
Configuration mode for the specified command. See Table 30 in the "Usage Guidelines" section for a list of options for this argument.
all
(Optional) Changes the privilege level for all the suboptions to the same level.
level level
Specifies the privilege level you are configuring for the specified command or commands. The level argument must be a number from 0 to 15.
reset
Resets the privilege level of the specified command or commands to the default and removes the privilege level configuration from the running configuration file.
Note
command-string
Command associated with the specified privilege level. If the all keyword is used, specifies the command and subcommands associated with the privilege level.
Defaults
User EXEC mode commands are privilege level 1.
Privileged EXEC mode and configuration mode commands are privilege level 15.
Command Modes
Global configuration
Command History
10.3
This command was introduced.
12.0(22)S, 12.2(13)T
The all keyword was added.
12.3(6), 12.3(6)T
The no form of the command performs the same function as the reset keyword.
Usage Guidelines
The password for a privilege level defined using the privilege global configuration command is configured using the enable secret command.
Level 0 can be used to specify a more-limited subset of commands for specific users or lines. For example, you can allow user "guest" to use only the show users and exit commands.
Note
When you set the privilege level for a command with multiple words, note that the commands starting with the first word will also have the specified access level. For example, if you set the show ip route command to level 15, the show commands and show ip commands are automatically set to privilege level 15—unless you set them individually to different levels. This is necessary because you can't execute, for example, the show ip command unless you have access to show commands.
To change the privilege level of a group of commands, use the all keyword. When you set a group of commands to a privilege level using the all keyword, all commands which match the beginning string are enabled for that level, and all commands which are available in submodes of that command are enabled for that level. For example, if you set the show ip keywords to level 5, show and ip will be changed to level 5 and all the options that follow the show ip string (such as show ip accounting, show ip aliases, show ip bgp, and so on) will be available at privilege level 5.
Table 30 shows some of the keyword options for the mode argument in the privilege command. The available mode keywords will vary depending on your hardware and software version. To see a list of available mode options on your system, use the privilege ? command.
.
Examples
The following example shows how to set the configure command to privilege level 14 and establish SecretPswd14 as the password users must enter to use level 14 commands:
privilege exec level 14 configureenable secret level 14 SecretPswd14The following example shows how to set the show and ip keywords to level 5. The suboptions coming under ip will also be allowed to users with privilege level 5 access:
Router(config)# privilege exec all level 5 show ipThe following two examples demonstate the difference in behavior between the no form of the command and the use of the reset keyword when using Cisco IOS software releases earlier than Releases 12.3(6) and Release 12.3(6)T.
Note
! show currently configured privilege commandsRouter# show running-config | include privprivilege configure all level 3 interfaceprivilege exec level 3 configure terminalprivilege exec level 3 configureRouter# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)# no privilege exec level 3 configure terminalRouter(config)# end! show currently configured privilege commandsRouter# show running-config | include privprivilege configure all level 3 interfaceprivilege exec level 15 configure terminalprivilege exec level 15 configureNote that in the show running-config output above, the privilege command for "configure terminal" still appears, but now has the default privilege level assigned.
To remove a previously configured privilege command entirely from the configuration, use the reset keyword, as shown in the following example:
! show currently configured privilege commandsRouter# show running-config | include privprivilege configure all level 3 interfaceprivilege exec level 3 configure terminalprivilege exec level 3 configureRouter# configure terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)# privilege exec reset configure terminalRouter(config)#Router# show running-config | include privprivilege configure all level 3 interfaceRouter#Related Commands
privilege level
To set the default privilege level for a line, use the privilege level command in line configuration mode. To restore the default user privilege level to the line, use the no form of this command.
privilege level level
no privilege level
Syntax Description
Defaults
Level 15 is the level of access permitted by the enable password.
Level 1 is normal EXEC-mode user privileges.
Command Modes
Line configuration
Command History
Usage Guidelines
Users can override the privilege level you set using this command by logging in to the line and enabling a different privilege level. They can lower the privilege level by using the disable command. If users know the password to a higher privilege level, they can use that password to enable the higher privilege level.
You can use level 0 to specify a subset of commands for specific users or lines. For example, you can allow user "guest" to use only the show users and exit commands.
You might specify a high level of privilege for your console line to restrict line usage.
Examples
The following example configures the auxiliary line for privilege level 5. Anyone using the auxiliary line has privilege level 5 by default:
line aux 0privilege level 5The following example sets all show ip commands, which includes all show commands, to privilege level 7:
privilege exec level 7 show ip routeThis is equivalent to the following command:
privilege exec level 7 showThe following example sets the show ip route to level 7 and the show and show ip commands to level 1:
privilege exec level 7 show ip routeprivilege exec level 1 show ipRelated Commands
enable password
Sets a local password to control access to various privilege levels.
qos-group
To apply a quality of service (QoS) group value to an Internet Security Association and Key Management Protocol (ISAKMP) profile, use the qos-group command in ISAKMP profile configuration mode. To disable the group value, use the no form of this command.
qos-group group-number
no qos-group group-number
Syntax Description
group-number
Number of the group number. The value ranges from 1 through 99. (There is no default value.)
Defaults
A QoS group value is not applied to an ISAKMP profile.
Command Modes
ISAKMP profile configuration
Command History
Usage Guidelines
If there is no matching QoS group set in a QoS policy, or if a service policy is not configured or applied to an interface that also has a crypto map applied, the ISAKMP profile setting (using the qos-group command) is not enforced.
Examples
The following example shows that QoS group "2" has been applied to the ISAKMP profile "class1":
Router (config)# crypto isakmp profile class1Router (conf-isa-prof)# qos-group 2! A profile is deemed incomplete until it has match identity statements.Related Commands
query certificate
To configure query certificates on a per-trustpoint basis, use the query certificate command in ca-trustpoint configuration mode. To disable creation of query certificates per trustpoint, use the no form of this command.
query certificate
no query certificate
Syntax Description
This command has no arguments or keywords.
Defaults
Query certificates are stored in NVRAM.
Command Modes
Ca-trustpoint configuration
Command History
Usage Guidelines
Normally, certain certificates are stored locally in the router's NVRAM, and each certificate uses a moderate amount of memory. To save NVRAM space, you can use this command to prevent certificates from being stored locally; instead, they are retrieved from a specified certification authority (CA) trustpoint when needed. This will save NVRAM space but could result in a slight performance impact.
Before you can configure this command, you must enable the crypto ca trustpoint command, which puts you in ca-trustpoint configuration mode.
Using the query certificate Command with a Specific Trustpoint
When the query certificate command is used, certificates associated with the specified truspoint will not be written into NVRAM, and the certificate query will be attempted during the next reload of the router.
Applying the Query Mode Globally
When the global command crypto ca certificate query command is used, the query certificate will be added to all trustpoints on the router. When the no crypto ca certicate query command is used, any previously query certificate configuration will be removed from all trustpoints, and any query in progress will be halted and the feature disabled.
Examples
The following example shows how to configure a trustpoint and initiate query mode for certificate authority:
crypto ca trustpoint trustpoint1enrollment url http://trustpoint1crl query ldap://trustpoint1query certificateexitRelated Commands
query url
Note
If you have to query the certificate revocation list (CRL) to ensure that the certificate of the peer has not been revoked and you have to provide the Lightweight Directory Access Protocol (LDAP) server information, use the query url command in ca-trustpoint configuration mode. To return to the default behavior, assuming that the CRL distribution point (CDP) has a complete (LDAP) URL, use no form of this command.
query url ldap://hostname:[port]
query url ldap://hostname:[port]
Syntax Description
Defaults
No enabled. If query url ldap://hostname:[port] is not enabled, the router assumes that the CDP that is embedded in the certificate is a complete URL (for example, ldap:myldap.cisco.com/CN=myCA,O=Cisco) and uses it to download the CRL.
If the port number is not configured, the default LDAP server port 389 will be used.
Command Modes
Ca-trustpoint configuration
Command History
11.3 T
This command was introduced.
12.2(8)T
This command was replaced by the crl query command.
Usage Guidelines
When Cisco IOS software tries to verify a peer certificate (for example, during Internet Key Exchange [IKE] or Secure Sockets Layer [SSL] handshake), it queries the CRL to ensure that the certificate has not been revoked. To locate the CRL, it first looks for the CDP extension in the certificate. If the extension exists, it is used to download the CRL. Otherwise, the Simple Certificate Enrollment Protocol (SCEP) GetCRL mechanism is used to query the CRL from the CA server directly (some CA servers do not support this method).
Cisco IOS software supports three types of CDP:
•
•
•
To locate the CRL, a complete URL needs to be formed. As a result, Example 3 and Example 4 still require the hostname and the port number. The ldap://hostname:[port} keywords and arguments are used to provide this information.
Note
Examples
The following example shows how to configure your router to query the CRL with the LDAP URL that is published by the CA named "bar":
crypto ca trustpoint mytpenrollment url http://bar.cisco.comquery url ldap://bar.cisco.com:3899Related Commands
crypto ca trustpoint
Declares the CA that your router should use.
revocation-check
Checks the revocation status of a certificate.
quit
To exit from the key-string mode while defining the Rivest, Shamir, and Adelman (RSA) manual key to be used for encryption or signatures during Internet Key Exchange (IKE) authentication, use the quit command in public key configuration mode.
quit
Syntax Description
This command has no arguments or keywords.
Defaults
No default behavior or values
Command Modes
Public key configuration
Command History
Usage Guidelines
Use this command to exit text mode while defining the RSA public key.
Examples
The following example shows that the RSA public key of an IP Security (IPSec) peer has been specified:
Router(config)# crypto keyring vpnkeyringRouter(conf-keyring)# rsa-pubkey name host.vpn.comRouter(config-pubkey-key)# address 10.5.5.1Router(config-pubkey)# key-stringRouter(config-pubkey)# 00302017 4A7D385B 1234EF29 335FC973Router(config-pubkey)# 2DD50A37 C4F4B0FD 9DADE748 429618D5Router(config-pubkey)# 18242BA3 2EDFBDD3 4296142A DDF7D3D8Router(config-pubkey)# 08407685 2F2190A0 0B43F1BD 9A8A26DBRouter(config-pubkey)# 07953829 791FCDE9 A98420F0 6A82045BRouter(config-pubkey)# 90288A26 DBC64468 7789F76E EE21Router(config-pubkey)# quitRouter(config-pubkey-key)# exitRouter(conf-keyring)# exitRelated Commands
address
Specifies the IP address of the remote RSA public key of the remote peer that you will manually configure.
key-string (IKE)
Specifies the RSA public key of a remote peer.
