GET VPN - part nine (exception)

Let’s consider scenario where we need to block traffic between some LANs but we don’t want to change proxy to not increase number of Security Association (SA).

My requirements are:

ACL should be the same - access-list 102 permit ip 20.0.0.0 0.255.255.255 20.0.0.0 0.255.255.255
permit LAN1-spoke1 (20.33.33.33) to LAN1-spoke2 (20.44.44.44)
deny LAN1-spoke1 (20.33.33.33) to LAN1-spoke3 (20.55.55.55)

One of the recommend method is ‘match’ statement under a crypto map:

access-list 120 deny   ip host 20.33.33.33 host 20.55.55.55

before I apply this access list I need to be sure I can ping hosts between sites:

R5#ping vrf RED 20.33.33.33 source 20.55.55.55
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 20.33.33.33, timeout is 2 seconds:
Packet sent with a source address of 20.55.55.55
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 96/98/100 ms
R5#

R4#ping vrf RED 20.33.33.33 source 20.44.44.44
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 20.33.33.33, timeout is 2 seconds:
Packet sent with a source address of 20.44.44.44
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 88/110/136 ms
R4#

As you see I can ping from both sites. Let’s apply the ACL:

R3#sh run int fa0/0.3
Building configuration...

Current configuration : 140 bytes
!
interface FastEthernet0/0.3
 encapsulation dot1Q 73
 ip vrf forwarding RED
 ip address 27.27.27.2 255.255.255.0
 crypto map MAPA-RED
end

R3#

Remember to choose the correct crypto map !

crypto map MAPA-RED 10 gdoi
 set group GDOI-GROUP-RED
 match address 120

and repeat the same test:

R5#ping vrf RED 20.33.33.33 source 20.55.55.55
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 20.33.33.33, timeout is 2 seconds:
Packet sent with a source address of 20.55.55.55
.....
Success rate is 0 percent (0/5)
R5#

R4#ping vrf RED 20.33.33.33 source 20.44.44.44
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 20.33.33.33, timeout is 2 seconds:
Packet sent with a source address of 20.44.44.44
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 72/106/132 ms
R4#

As you see above the new exception works as expected. More information about the GET VPN solution you find here:

http://www.cisco.com/c/en/us/products/collateral/security/group-encrypted-transport-vpn/deployment_guide_c07_554713.html

Comments

What should you know about HA 'override enabled' setting on Fortigate?

High availability is mandatory in most of today's network designs. Only very small companies or branches can run their business without redundancy. When you have Fortigate firewall in your network you have many options to increase network availability. You can use Fortigate Clustering Protocol ( FGCP ) or Virtual Router Redundancy Protocol ( VRRP ). FGCP has two modes: 'override' disabled (default) and 'override' enabled . I'm not going to explain how to set up HA as you can find many resources on Fortinet websites: https://cookbook.fortinet.com/high-availability-two-fortigates-56/ https://cookbook.fortinet.com/high-availability-with-fgcp-56/ Let's recap what is the main difference between them. The default HA setting is 'override' disabled and this is an order of selection an active unit: 1) number of monitored interfaces - when both units have the same number of working (up) interfaces check next parameter 2) HA uptime - an ...

FortiGate and GRE tunnel

Recently I worked on one project where a client requested to re-route web traffic to the GRE tunnel to perform traffic inspection. I would like to share with you what is required if you configure it on FortiGate. We need a new GRE interface and policy base routing (PBR) to change the route for specific source IPs. Of course you need firewall policies to permit the traffic. Let's start with GRE interface. Unfortunately you can't configure it using the GUI, only CLI is the option: config system gre-tunnel edit "gre1" set interface "port1" set local-gw 55.55.55.55 set remote-gw 44.44.44.44 next end When the end peer is Cisco router, you need to set the IP for the GRE interface: config system interface edit gre1 set ip 192.168.10.10 255.255.255.255 set remote-ip192.168.10.20 end In next step we need to fix routing. We need the alternate path via GRE but to keep the route in the active routing table you need to set the same AD (adminis...

Data Leak Prevention (DLP) on Fortigate

Today I would like to present one interesting feature you may find on your Fortigate - Data Leak Prevention. I know there are much better, dedicated solutions on the market but in certain situations the DLP feature available on FortiOS is good enough. Why you should use it? This is very important to say: the DLP in such deployment (on Fortigate) can't protect your data against every data leak. Users in your network with his/her mobile can easily take a photo of any document. Why we should still consider it? It is a good (and easy to deploy) method to prevent users' mistakes. It happened hundreds of time when a user attached a wrong file. Sound familiar? Using the DLP you can create policies which stop such leak. Let me show you how you can configure it. Step #1 First, you have to check if DLP is enabled in a "Feature Visibility" and "Security Features" section: When you do not see the feature, make sure your Fortigate works in a proxy-ba...

myITmicroblog

Search This Blog