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Adrien_Legros_1's avatar
Adrien_Legros_1
Icon for Altostratus rankAltostratus
Dec 12, 2008

Keep Source IP & BIgIP as Default gateway

Hello,

 

 

I'd like to keep the source IP of my client behind the BigIP. F5 told me that I should define the BigIP as the default gateway for our servers. But which IP should be the default gateway ? And what do I have to change on the BigIP ? I've readen that I have to create a new VS ? I have only 2 vlans on my bigip: one for sync the other for all the applications. For the applications, the IPS are in 2 subnets.

 

Please some can tell me what I should to configure on the BigIP to have this working well ?

 

Thanks for your help
config
design
  • James_Quinby_46's avatar
    James_Quinby_46
    Historic F5 Account
    Dec 12, 2008
    A typical method is to use the LTM's self IP as the gateway address. If you have an HA pair, use the float IP so that it's always available to your back-end servers.

     

     

    If your network topology requires the use of a SNAT, you can preserve (for HTTP apps, in any case) client source IP via the "X-Forwarded-For" header.

     

     

    Using the BigIP as a gateway ('routed' mode) is how most folks tend to deploy in production. For testing and evaluation purposes, a SNAT'ed deployment ('one-armed' mode) is used because it's the least intrusive to the environment. Using routed mode will require you to change the default GW of any hosts that reside 'behind' the BigIP.