300-730 SVPN: Implementing Secure Solutions with Virtual Private NetworksDemo

The Clientless SSL VPN portal provides built-in access to HTTP/HTTPS web resources and CIFS file shares. ICA, VNC, and RDP depend on separately configured client-server plug-ins rather than being enabled by default.

Advanced Endpoint Assessment enhances Host Scan with remediation actions that can attempt to update noncompliant computers to meet required version requirements, enabling the endpoint to satisfy the enterprise security policy.

Route-based IPsec virtual tunnel interfaces create an automatically generated Tunnel<number>-head-0 crypto-map entry and commonly use any-to-any IPsec traffic selectors. FlexVPN is built on this tunnel-interface/VTI model, so both FlexVPN and VTI can produce this form of IPsec SA output. GRE and DMVPN tunnel protection instead identifies GRE traffic with IP protocol 47, whereas a conventional crypto map is typically associated with a physical interface and ACL-selected traffic.

A FlexVPN server supports an IPv6 dVTI session when its IKEv2 profile is associated with a virtual template and the virtual template is configured for tunnel mode ipsec ipv6. The IPv6 address pool, DNS servers, and subnet ACL are supplied through the IKEv2 authorization policy; authentication is certificate-based RSA signatures with local AAA group authorization.

A Clientless SSL VPN portal displays a URL list when that list is applied in the group policy’s WebVPN attributes. The url-list setting in group-policy ... attributes → webvpn controls the servers and URLs made available to users of that policy.

IPsec is limited to unicast peer security associations, so it does not natively carry multicast traffic. GRE encapsulates multicast packets, after which IPsec encrypts the unicast GRE tunnel traffic. Cisco IOS routers support this GRE-over-IPsec design.

The Employee connection profile inherits the default group policy, whose vpn-tunnel-protocol setting allows only ssl-clientless. Its webvpn-attributes also identify it as a clientless SSL VPN profile. AnyConnect is enabled globally, but it is not allowed by the inherited group policy for this profile. Cisco documents that permitted clientless or AnyConnect connections are controlled by the group-policy or username vpn-tunnel-protocol setting.

TS_UNACCEPTABLE indicates that the received IKEv2 traffic selectors do not match an IPsec policy. The log explicitly states that no IPsec policy was found for the received TS, identifying an interesting-traffic (crypto ACL/traffic-selector) mismatch.

A grayed-out clientless SSL VPN bookmark indicates that the ASA cannot resolve the bookmarked website’s hostname through DNS. The ASA therefore cannot provide the URL to the user.

An IKE security association requires compatible ISAKMP policy authentication, so the spoke must use pre-shared-key authentication to match the hub. NHRP registration also requires matching authentication when the hub is configured with an NHRP authentication key; configuring cisco123 on the spoke satisfies that requirement. The existing spoke NHS protocol address (10.0.0.1) and NBMA address (172.16.18.1) are already mapped correctly.

The local user database is already selected by using LOCAL as the AAA server group. An AnyConnect SSL VPN connection also requires the group policy to permit the SSL VPN client protocol; with that protocol disabled, the client cannot establish an SSL VPN session. Cisco documents that LOCAL specifies the internal user database, while the group policy controls enabled VPN client protocols. Cisco Secure Firewall ASA VPN Configuration Guide

A large received replay-failure count means the IPsec anti-replay check is discarding packets whose sequence numbers fall outside its acceptable window. Increasing or otherwise adjusting the IPsec replay window accommodates packet reordering and prevents those packets from being dropped.

show ip nhrp traffic displays NHRP traffic statistics, including registration requests and replies. show dmvpn detail displays detailed DMVPN session information, including Next Hop Server status and NHRP-related session details. Together, they reveal whether NHRP registration requests are being sent and whether replies are being received.

A webtype ACL restricts the URLs and web resources available through a clientless SSL VPN. Applying an appropriate webtype ACL to the sales group policy prevents its users from accessing the finance department’s database server.

authentication aaa configures AAA username/password authentication for the connection profile. group-alias General enable publishes General as a selectable tunnel-group alias on the AnyConnect login page (with tunnel-group-list enabled globally). A group URL instead automatically selects its associated connection profile when a user accesses that URL.

DMVPN Phase 3 requires ip nhrp redirect on the hub to inform a source spoke of a better spoke-to-spoke path. The configured ip nhrp shortcut is the complementary spoke-side feature that processes the redirect and enables the direct NHRP shortcut.

A FlexVPN hub uses a dynamic virtual tunnel interface configured with interface virtual-template. For each incoming spoke-to-hub connection, it creates a corresponding Virtual-Access interface from that template to terminate the tunnel. ip nhrp redirect supports spoke-to-spoke tunnel optimization and is not required when such tunnels are prohibited.

For Cisco router IKEv2 remote access, split-tunnel routes are assigned in an IKEv2 authorization policy by using route set access-list to reference the split-tunnel ACL. The authorization policy supplies these route attributes to the remote client.

The RDP2 plug-in supports Remote Desktop access to Windows Vista Terminal Services, while the VNC plug-in provides graphical remote control of a computer running a VNC service. Telnet and SSH are command-line protocols, and ICA is intended for Citrix MetaFrame services.

Additional IKEv2 Child SAs are created with the CREATE_CHILD_SA exchange. Its request and response include the TSi and TSr payloads that propose and return the negotiated traffic selectors.

For an IPsec/IKEv2 AnyConnect connection to an ASA, the User Group field must contain the exact name of the ASA connection profile (tunnel group).

TS_UNACCEPTABLE indicates that the received IKEv2 traffic selectors do not match a configured IPsec policy. In a policy-based ASA site-to-site VPN, the crypto access list defines those protected source and destination networks, so the crypto access lists must match as mirrored local/remote pairs on the two VPN devices. Cisco documents this error when no matching IPsec policy exists for the received traffic selectors.

Cisco ASA Smart Tunnel supports applications that are not supported by the clientless SSL VPN core rewriter. Configuring a Smart Tunnel for the affected web server allows access through the browser-based clientless SSL VPN session without relying on the failing URL/content rewrite process.

A full-tunnel SSL VPN policy sends all client traffic through the ASA. The ASA then applies PAT using its outside-interface address, so an Internet IP-address lookup sees 3.3.3.3. Cisco documents that the tunnelall split-tunnel policy sends all traffic through the tunnel.