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cwkim_261931's avatar
cwkim_261931
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Jan 03, 2019

Is SRC MAC(last hop mac) changed in connections when other router send packet?

Hi,

 

I used auto last hop.

 

And I want to know that src mac(last hop mac) is changed when other router send packet instead of main router.

 

ex) router A MAC : AA router B MAC : BB BIG-IP MAC : CC

 

router A <-1-> BIG-IP <--> Server

 

(before) <-1-> src mac : AA dst mac : CC Create a connection(last hop mac : AA)

 

(after) <-1-> src mac : BB dst mac : CC Reuse a connection(Is last hop mac changed "BB"?!)

 

2 Replies

  • Hi cwkim,

     

    I'm not 100% sure about the example you've described, but I think you're trying to see what would happen if you have redundant upstream routers and one fails?

     

    Check out this KB article which describes how to configure this setup.

     

    https://support.f5.com/csp/article/K2211

     

    The short answer is if the router fails, it will continue to send traffic to the original router per the article.

     

    --D

     

  • The answer is NO

     

    Source MAC address doesn’t change in connection table. The connection will fail!

     

    If you want to support Mac failover, you have to create a gateway pool with both routers and add this pool as last hop pool in the virtual server!