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cmoates's avatar
cmoates
Icon for Nimbostratus rankNimbostratus
Feb 10, 2008

Simple routing issue?

I'm having a bit of trouble understanding what small bit of information I'm missing that's causing me a bunch of grief. I've attached a network diagram to this message to help illustrate my configuration.

 

 

I have already set up the virtual server for forwarding, and this appears to work if and only if I have no NAT set up to get to the outside world. As soon as I set up a NAT to get to the outside world, then when I ping between 10.0.10.x and 10.0.11.x I see the public IP when I get the ICMP request (as viewed via tcpdump).

 

 

I can't imagine that this is that difficult; can anyone help me to understand what I'm overlooking? I have the forwarding VS set up for all VLANs, and when I set up the NAT, I set it to only be on the external VLAN.

 

 

Any suggestions?
config
design

2 Replies

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  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Feb 11, 2008
    I've never had much success with NATs and VIPs together. In general, it's more effective to use a virtual server to pass the traffic. If you want a one-to-one correlation between the virtual IP and the host, you can define a VIP pointing to a pool with the single host. If you want to allow all ports, you can define the VIP and the pool member on port 0 (any port).

     

     

    Aaron
  • kykong_107132's avatar
    kykong_107132
    Icon for Nimbostratus rankNimbostratus
    Feb 11, 2008
    Hi,

     

    Normally I'll use SNAT automap for internet access instead of NAT. you can try to create a wildcard_vs with LTM default gateway as pool member. enable automap for this wildcard_vs. lastly, delete the NAT. following is the sample of the configuration.

     

     

    pool default_gw {

     

    member 72.x.x.1:any

     

    }

     

     

    virtual wildcard_vs {

     

    destination any:any

     

    mask none

     

    pool default_gw

     

    snat automap

     

    }

     

     

    regards,

     

    KY