When using a Cisco ASA with the AnyConnect VPN Client software in some instances it is useful to assign the same static IP address to a client whenever they connect to the VPN. Within Active Directory you can configure per user a static IP address and use this IP address whenever the user connects to the VPN. The RADIUS Server (in this instance Cisco ISE 2.0) can be configured to query the attribute in AD which is the” msRADIUSFramedIPAddress” value and assign to the client whenever they connect.
This blog post describes the steps to modify the configuration of ASA/ISE/AD and assumes the Cisco ASA is already properly configured and users can successfully authenticate using the AnyConnect VPN client and receive an IP address from the IP Address Pool. Cisco ISE is defined as the RADIUS Server with Active Directory defined as the External Identity Source.
Continue reading Cisco ASA AnyConnect VPN with Static Client IP Address
This post details the configuration on how to configure a DMVPN Phase 3 VPN in a Dual Hub Single Cloud. I previously wrote a post on configuring DMVPN Phase 2, refer to this post for more detailed information on configuring DMVPN.
As per most previous posts GNS3 was used to lab the configuration. I had to use the Advanced Security IOS image “c7200-advsecurityk9-mz.152-4.M7” instead of my normal Advanced IP Services IOS image “c7200-advipservicesk9-mz.152-4.S4” because that version does not support NHRP redirect required for DMVPN Phase 3. The error received when configuring NHRP redirect is: % NHRP-WARNING: ‘ip nhrp redirect’ failed to initialise.
This post covers the following:
Front Door VRF
Dual DMVPN Hub configuration
DMVPN Spoke configuration
DMVPN NHS Clustering (dual active Hubs and Active/Standby Hub)
- DMVPN Phase 3
The router default ISAKMP Policy, IPSec Transform Set and IPSec Profile were used and therefore not covered in this post. This previous post covers ISAKMP and IPSec Policy/Profile creation.
The lab scenario has 6 x Cisco IOS 15.2(4) routers as represented in the diagram below.
Continue reading Configuring DMVPN Phase 3 Dual Hub
This blog post provides the simple configuration information to setup a Site-to-Site VPN between two Cisco ASA firewalls using the IKEv2 protocol.
The following lab scenario was setup in GNS3 using the following images:
- Cisco ASAv version 9.5(2)
- Cisco IOS version 15.2(4)
A VPN will be setup between the 2 Cisco ASA firewalls (ASAv-1 and ASAv-2). The 2 routers (R1 and R2) will act as hosts in the local networks in order to generate traffic to initiate the VPN tunnel on demand.
Continue reading Configuring IKEv2 Site-to-Site VPN on Cisco ASA
In a FlexVPN Hub and Spoke design spoke routers are configured with a normal static VTI with the tunnel destination of the Hub’s IP address, the Hub however is configured with a Dynamic VTI. The DVTI on the Hub router is not configured with a static mapping to the peer’s IP address. The VTI on the Hub is created dynamically from a preconfigured tunnel template “virtual-template” when a tunnel is initiated by the spoke router/peer. The dynamic tunnel spawns a separate “virtual-access” interface for each spoke tunnel, inheriting the configuration from the cloned the template.
Continue reading Configuring Cisco FlexVPN Hub-and-Spoke
As mentioned in the previous blog post when configuring FlexVPN configuration can be minimized by using the Smart Defaults, they comprises of default configurations for IKEv2 Proposal, IKEv2 Policy, IPSec Profile and Transform Set. This post provides a simple configuration example when using Smart Defaults and when using custom configurations.
Configuration Example – FlexVPN SVTI with Smart Defaults
This simple lab configuration is to setup a SVTI Site-to-Site VPN between 2 Cisco IOS routers.
Continue reading Configuring Cisco FlexVPN SVTI
FlexVPN is a framework to configure IPSec VPNs on Cisco IOS devices; it was created to simplify the deployment of VPN solutions of all type (Site-to-Site, Remote Access etc). It uses a common configuration template for all VPN types. FlexVPN is based on IKEv2 and does not support IKEv1.
- IKEv2 is more secure than IKEv1 because it supports the latest Suite B cryptographic algorithms
- Built-in support for Dead Peer Detection (DPD) and NAT-Traversal
- Is resistant to DoS attacks
- Consolidated IKEv1 main and aggressive modes into one method, called “initial”
- Supports more authentication methods; in addition to PSK, certificates it also supports EAP authentication.
- XAUTH not used in IKEv2, EAP is used for authentication instead: EAP Tunneling: EAP-TLS, EAP-PEAP, EAP-PSK, EAP Non-Tunnelling: EAP-MSCHAPv2, EAP-MD5, EAP-GTC and
Continue reading Cisco FlexVPN Overview
IPSec VTIs (Virtual Tunnels Interfaces) simplifies the configuration of a VPN compared to using crypto maps or GRE IPSec Tunnels. A benefit of using VTIs does not require of tying a configuration to a physical interface, rather allowing bespoke configuration per VTI. You can use a dynamic routing protocol (EIGRP, OSPF etc) or QoS defined per VTI.
VTI Configuration Example using defaults
To setup a basic VTI based site-to-site VPN you can use the Crypto defaults (ISAKMP Policy, IPSec Transform Set and IPSec Profile), in addition to the VTI the only crypto configuration needs to be a Pre-Shared Key.
Step 1 – Define a Pre-Shared Key
R1(config)# crypto isakmp key cisco123 address 0.0.0.0
Step 2 – Configure Tunnel Interface
R1(config)# interface tunnel 0
R1(config-if)# ip address 10.10.0.1 255.255.255.0
R1(config-if)# tunnel source fastethernet 0/0
R1(config-if)# tunnel destination 126.96.36.199
R1(config-if)# tunnel mode ipsec ipv4
R1(config-if)# tunnel protection ipsec profile default
Continue reading Configuring a Cisco IOS VTI based tunnel