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Bunty_384462's avatar
Bunty_384462
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Feb 22, 2019

Can we swapped VIPs ip addresses in F5 ?

Hello All, I just would like to know can we swapped the VIPs ip address ?   For example   1.1.1.1 --> pool ---> servers(old) 2.2.2.2 ---> pool ---> servers (new)   I want to swap these two V...
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  • AceDawg_204810's avatar
    AceDawg_204810
    Feb 22, 2019

    If I'm understanding your question correctly, you cannot have two VIPs with the same IP address and port. There is a precedence that the F5 uses when accepting network traffic:

     

    1. Existing session in session table
    2. Packet Filter
    3. Virtual Server (https://support.f5.com/csp/article/K14800)
    4. SNAT
    5. NAT
    6. Self-IP
    7. Deny

    The third item on this list->Virtual Server has a precedence as well: https://support.f5.com/csp/article/K14800. That precedence would not allow two virtual servers to share the same IP address and port.

     

AceDawg1's avatar
AceDawg1
Icon for Nimbostratus rankNimbostratus
Feb 22, 2019

If I'm understanding your question correctly, you cannot have two VIPs with the same IP address and port. There is a precedence that the F5 uses when accepting network traffic:

 

  1. Existing session in session table
  2. Packet Filter
  3. Virtual Server (https://support.f5.com/csp/article/K14800)
  4. SNAT
  5. NAT
  6. Self-IP
  7. Deny

The third item on this list->Virtual Server has a precedence as well: https://support.f5.com/csp/article/K14800. That precedence would not allow two virtual servers to share the same IP address and port.

 

  • Bunty_384462's avatar
    Bunty_384462
    Icon for Nimbostratus rankNimbostratus
    Feb 22, 2019

    Thanks for this information and your prompt reply AceDawg. But in my case how we can swap VIPs ip addresses in case we want to do the same. Kindly suggest.thx

     

  • AceDawg1's avatar
    AceDawg1
    Icon for Nimbostratus rankNimbostratus
    Feb 22, 2019

    Since you can't have two virtual servers with the same VIP and port, I would:

     

    1. Configure virtual server A with a fake IP address
    2. Configure virtual server B with the VIP address from virtual server A
    3. Configure virtual server A with the VIP address from virtual server

    Let me know if this does/doesn't address your issue or if I'm misunderstanding.

     

  • Bunty_384462's avatar
    Bunty_384462
    Icon for Nimbostratus rankNimbostratus
    Feb 22, 2019

    Thanks AceDawg ,even my understanding was the same like we need to use dummy ip to get this done. Thanks for your support. Cheers

     

  • AceDawg1's avatar
    AceDawg1
    Icon for Nimbostratus rankNimbostratus
    Feb 22, 2019

    If you agree with the approach, feel free to up vote or "Accept" the response.