Cisco ASA: Routing packets based on where the connections started from
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Published on 2010-03-09T06:08:18Z
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2010/03/09
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We have a Cisco ASA 5505 (version 8.2(2)) with three interfaces:
outside: IP address 11.11.11.11, this is the default route inside: IP address 10.1.1.1, this is the local subnet newlink: 22.22.22.22, this is a new internet connection.
We need to move VPN users from the 11.11.11.11 address to the 22.22.22.22 address, and we're using SSH on the ASA as to test and sort out the routing.
The problem we have is this:
If we define a particular IP as being on a static route out the newlink interface then it can SSH to 22.22.22.22 fine. If we do not define a static route then the traffic hits the ASA, but the return traffic does not come back over newlink; presumably it gets sent over the outside interfcae as that is the default route. We can't define a static route for each remote endpoint because there are dialup VPN users, who obviously change IP a lot
What we need to do is configure the ASA so if a connection comes in on the newlink interface then the outgoing packets for that go over the newlink interface, not the default route. With iptables this should be do-able by marking the connection and doing mark-routing, but what is the equivalent for a Cisco ASA?
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