300-730 Implementing Secure Solutions with Virtual Private Networks (SVPN) Questions and Answers

IKE Message from X.X.X.X Failed its Sanity Check or is Malformed

This debug error appears if the pre-shared keys on the peers do not match. In order to fix this issue, check the pre-shared keys on both sides.

1d00H:%CRPTO-4-IKMP_BAD_MESSAGE: IKE message from 198.51.100.1 failed its

sanity check or is malformed

https://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/5409-ipsec-debug-00.html#anc17

The auto-signon command is a single sign-on method for users of clientless SSL VPN sessions. It passes the login credentials (username and password) to internal servers for authentication using NTLM authentication, basic authentication, or both. Multiple auto-signon commands can be entered and are processed according to the input order (early commands take precedence).

https://www.cisco.com/c/en/us/td/docs/security/asa/asa916/configuration/vpn/asa-916-vpn-config/webvpn-configure-policy-groups.html#ID-2439-00001438

https://www.cisco.com/c/en/us/td/docs/security/asa/asa94/config-guides/asdm74/vpn/asdm-74-vpn-config/webvpn-troubleshooting.html

The following Clientless SSL VPN features will not work when the http-only-cookie command is

enabled:

• Java plug-ins

• Java rewriter

• Port forwarding

• File browser

• Sharepoint features that require desktop applications (for example, MS Office applications)

• AnyConnect Web launch

• Citrix Receiver, XenDesktop, and Xenon

• Other non-browser-based and browser plugin-based applications

The correct answer is A. Specify the trace using the -T option after the capture-traffic command. According to the document Use Firepower Threat Defense Captures and Packet Tracer, the capture-traffic command allows you to capture packets on the Snort engine domain of the FTD device. However, by default, it only shows the packet headers and does not include the Snort detection actions. To see the Snort detection actions, you need to use the -T option, which enables tracing. For example:

capture-traffic -T

This will show the packet headers along with the Snort verdicts, such as allow, block, or replace. You can also use other options to filter or save the capture output1.

B. Performing the trace within the Cisco FMC GUI instead of the Cisco FMC CLI is not a valid option, because the FMC GUI does not support packet capture or tracing on the FTD device. You can only use the FMC GUI to view and export captures that are taken on the FTD CLI1.

C. Using the verbose option as a part of the capture-traffic command is not a valid option, because there is no verbose option for this command. The verbose option is only available for the capture command, which is used to capture packets on the LINA engine domain of the FTD device1.

D. Using the capture command and specifying the trace option to get the required information is not a valid option, because the capture command does not have a trace option. The capture command allows you to capture packets on the LINA engine domain of the FTD device, but it does not show the Snort detection actions. The trace option is only available for the packet-tracer command, which is used to simulate a packet going through the FTD device and show its processing steps1.

https://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/113594-trouble-ios-ike-00.html#anc12

https://www.cisco.com/c/en/us/td/docs/security/asa/asa92/configuration/general/asa-general-cli/acl-webtype.pdf

The correct answer is C. promiscuous mode. In promiscuous mode, the Cisco IPS appliance operates as a passive device that monitors a copy of the network traffic and analyzes it for malicious activity. The appliance does not affect the traffic flow, but it can generate alerts, logs, and reports based on the configured security policy. Promiscuous mode is useful for initial deployment and baseline analysis, as well as for monitoring low-risk segments of the network12.

A. failsafe mode is a feature that determines how the appliance behaves when a hardware or software failure occurs. It does not affect the normal traffic flow or analysis3. B. inline tap mode is a variation of inline mode that allows the appliance to pass traffic without inspection in case of a power failure or a software crash. It does not allow the appliance to collect data without affecting traffic4. D. bypass mode is a feature that enables the appliance to bypass traffic without inspection when it is overloaded or under maintenance. It does not allow the appliance to analyze traffic and generate alerts.

1: How the Sensor Functions 2: Cisco ASA IPS Module Quick Start Guide 3: Failsafe Mode 4: Inline Tap Mode : Bypass Mode

To fix the problem with the IKEv2 site-to-site tunnel between an ASA and a remote peer based on the debug output, you should ensure that the crypto IPsec policy matches on both VPN devices. The debug output indicates that the crypto policies on the two VPN devices are mismatched, which is preventing the tunnel from building successfully. Installing the correct certificate to validate the peer, correcting the crypto access list on both VPN devices, and specifying the peer IP address in the tunnel group name will not fix the problem.

HSRP (Hot Standby Router Protocol). HSRP is a Cisco proprietary protocol that provides stateful failover for IPsec virtual private networks (VPNs). It is used to create a virtual router in order to provide redundancy in the event of an IPsec VPN failure. HSRP works by assigning a single primary router to manage the connection and forwarding traffic to the secondary router if the primary router fails.

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_conn_vpnav/configuration/15-mt/sec-vpn-availability-15-mt-book/sec-state-fail-ipsec.html

https://www.cisco.com/en/US/technologies/tk583/tk372/technologies_white_paper0900aecd8029d629.html

https://www.cisco.com/c/en/us/support/docs/security/dynamic-multipoint-vpn-dmvpn/111976-dmvpn-troubleshoot-00.html

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_conn_ike2vpn/configuration/15-mt/sec-flex-vpn-15-mt-book/sec-flex-spoke.html

https://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/216276-configure-route-based-site-to-site-vpn-t.html#anc6

The IKEv2 CREATE_CHILD_SA packet is used to establish a new security association (SA) between two peers. This packet contains the details of the exchange, including the traffic selectors, the cryptographic algorithms and keys to be used, and any other relevant information

DMVPN disables the EIRGP next-hop-self with "no ip next-hop-self eigrp xxx" in DMVPN phase 2, and to go from Phase 2 to 3 you need use the NHRP protocol, and again enable EIRGP next-hop-self with "ip next-hop-self eigrp 134" under the tunnel interface https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_conn_dmvpn/configuration/15-mt/sec-conn-dmvpn-15-mt-book/sec-conn-dmvpn-dmvpn.html#GUID-BF561439-BCC0-4AAF-80D9-1F7876CB7B81

https://www.globalknowledge.com/us-en/resources/resource-library/articles/understanding-next-hop-resolution-protocol-commands/

Reverse route injection (RRI) is a method that dynamically installs the network routes for remote tunnel endpoints. The RRI feature allows the router to automatically learn the routes for the remote networks and automatically install these routes into the routing table. This eliminates the need for the administrator to manually configure and maintain the routes for the remote networks. This feature is commonly used in VPN environments, where the router at the VPN endpoint needs to learn the routes for the remote networks behind the other VPN endpoint. The other options such as policy-based routing, CEF, and route filtering are not used to dynamically install the network routes for remote tunnel endpoints

KS (key server) is ‘caretaker’ of the GM group. Group registrations and authentication of GMs is taken care of by KS server. Any GM who wants to join the group is required to be successfully authenticated in the group and sends encryption keys and policy to be used within the group.

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https://ipwithease.com/introduction-to-getvpn/

On a FlexVPN hub-and-spoke topology where spoke-to-spoke tunnels are not allowed, the command that is needed for the hub to be able to terminate FlexVPN tunnels is interface virtual-template. The interface virtual-template command is used to configure a virtual template interface which provides a secure tunnel for FlexVPN connections. The other commands listed - interface virtual-access, ip nhrp redirect, and interface tunnel - are not related to FlexVPN and are not used to terminate FlexVPN tunnels.

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_conn_ikevpn/configuration/xe-3s/sec-ike-for-ipsec-vpns-xe-3s-book/sec-call-addmsn-ike.html

The correct answer is D. IKEv2 profile. A FlexVPN tunnel requires an IKEv2 profile to define the parameters for the IKEv2 negotiation and the IPsec security association. The IKEv2 profile references the IKEv2 keyring, the authentication method, the identity of the peers, and other options. The IKEv2 profile is then applied to a virtual tunnel interface (VTI) or a dynamic virtual tunnel interface (DVTI) to protect the tunnel with IPsec12. An EAP configuration is used for authentication with Extensible Authentication Protocol (EAP), which is optional for FlexVPN3. A multipoint GRE tunnel interface is used for DMVPN, not FlexVPN. An IKEv1 policy is used for IKEv1, not IKEv2, which is the protocol for FlexVPN.