Posts about Cisco VPN written by cjcott01. I thought I would blog on this. It could be useful for someone who might have an IOS router instead of an ASA and need to create a IPSEC Site-to-Site VPN to a remote peer, then NAT VPN traffic to a different address or subnet if needed, or the local subnets conflict with each other.

VPN Traffic Flow Through ASA I have a VPN tunnel that's coming up ok, capture shows the traffic hitting the inside interface, but nothing is getting to the next hop. When I do a packet trace the traffic fails: Hi there I'm trying to use a VPN connection that's been working on an ASA for months on ASA9.1(2). I've upgraded to ASA9.1(6)11 and it's stopped working. These are remote ASA5505s making an IPSEC-RA connection to a headend 5520. I can roll back and forward from 9.1(2) and 9.1(6)11 and whilst the co In one of the articles I wrote about VPN between overlapping subnets, I promised to write on the flow of packets through a Cisco ASA especially as it relates to NAT and route-lookup. In this article, I will focus on general packet flow through the ASA. In the next article, I will drill down into the specifics of NAT and route-lookup. Cisco ASA Packet Process Algorithm. The interface that receives the packet is called the ingress interface and the interface through which the packet exits is called the egress interface. When referring to the packet flow through any device, it can be easily simplified by looking at the task in terms of these two interfaces. Petes-ASA(config)# packet-tracer input inside tcp 192.168.254.1 www 10.254.254.10 www Phase: 1 Type: ROUTE-LOOKUP Subtype: input Result: ALLOW Config: Additional Information: in 0.0.0.0 0.0.0.0 outside Phase: 2 Type: UN-NAT Subtype: static Result: ALLOW Config: nat (inside,outside) source static Obj-SiteA Obj-SiteA destination static Obj-SiteB Obj-SiteB no-proxy-arp route-lookup Additional Nov 15, 2011 · Packet flow through a Cisco ASA. with 16 comments As I was reading my Cisco Firewalls book I found this picture (very early on to) concerning how a Cisco ASA handles traffic passing through the device and the logic behind it. it’s a chart worth paying attention to in my opinion.

I am very confused with the packet flow of checkpoint firewall. I have seen in many places fw ctl chain is referred to understand the packet flow but I am not able to interpret it. Could someone please help me in understanding the packet flow in terms of. SAM. IP spoofing. Policy lookup. Dst NAT. route lookup. Src NAT. VPN. etc..

The ASA will allow users in DMZ2 to access the DNS server in DMZ1. We first simulate web browsing traffic initiated from a host on the internet with IP 10.1.1.200, trying to reach the web server on port 80. The following command sates: “Generate a fake packet and push it through to the ASA’s outside interface in the inbound direction. This packet has both a S (syn) and an ack. Notice here the source of this packet is the webserver 2.2.2.2. To really tell who initiated this flow originally look at the ports. You see that the source IP is coming from port 80 and it s going to port 12869. This tells us this is return traffic and the original request was really TO port 80.

Use AnyConnect browser link to call connect to VPN: This is the option that I used. This requires enabling external control of AnyConnect, and is a potential security risk. An attacker could create a link to connect to a VPN, tunnel all traffic, and use it for a man-in-the-middle attack. For my use case, the benefit outweighs the risk.

Apr 24, 2012 Packet-tracer in Cisco ASA – simulated traffic | Network May 30, 2012 show asp drop Command Usage - Cisco