Help me understand this network configuration.
Posted on 2012-03-20
While I have knowledge and experience, I'm no networking expert. I'm having trouble wrapping my head around this configuration, as it seems to be looping.
Two pieces of hardware, a Cisco 3750, and an ASA5520. I'd rather not post the full configs. The 3750 is handling all of the internal VLAN routing. Here are what I believe to be the relevant commands:
ip address 10.1.101.2 255.255.255.0
ip route 0.0.0.0 0.0.0.0 10.1.101.1
ip address 72.x.x.x 255.255.255.224
ip address 10.1.101.1 255.255.255.0
global (outside) 72.x.x.x netmask 0.0.0.0
nat (inside) 101 0.0.0.0 0.0.0.0
route outside 0.0.0.0 0.0.0.0 72.x.x.x 1
route inside 10.1.1.0 255.255.255.0 10.1.101.2 1
route inside 10.1.20.0 255.255.255.0 10.1.101.2 1
route inside 10.1.21.0 255.255.255.0 10.1.101.2 1
There is a cable connecting Gi0/1/12 to Gi0/1, passing through a passive web filter. It seems like the 3750 is sending everything to the ASA, which is sending everything back to port 12 on the 3750?
No, no, I'm wrong. I thought the 3750 was doing the routing, but really it's the ASA. Right? Either way, this seems very inefficient. If that's the case, it seems like all our internal traffic is passing through the web filter twice! Surely that's exponentially increasing the load on the filter!
Anyhow, any insight anyone can offer is appreciated. If I need to provide further info, just let me know.