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Ahmad_Mohaidat_'s avatar
Ahmad_Mohaidat_
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Dec 31, 2013

LTM routing concern.

Dears,

 

I need your kind advise regarding the following setup , we have two LTMs in Active/standby mode and we are trying to use them to load balance the traffic that is going to multiple servers in multiple VLANs.

 

The setup is simply like the following:

 

 

we have two groups of servers , each in separate vlan and thus has a unique gateway , the gateway for vlan 1 (in RED) is configured on Router A , and the gateway for VLAN 2 (in GREEN) is configured on another router (Router B).

 

in our scenario we need to keep the gateway on the servers to be the router (not the LTM) and SNAT mode needs to be applied.

 

The configuration that we applied is:

 

1- configured two different VLANs each with its own self-ip 2- configured two virtual servers each for one VLAN.

 

My concern is:

 

From routing point of view , is there any special configuration that we need to add to the LTM ? how the LTM will distinguish the traffic that is coming from Router A or router B ?

 

Best Regards, Ahmad

 

1 Reply

  • how the LTM will distinguish the traffic that is coming from Router A or router B ?

     

    do you concern about return traffic from f5 to client?

     

    if yes, there is feature called auto lasthop which is enabled by default. it will send return traffic to mac address it was coming from (i.e. route on f5 is not required).

     

    sol13876: Overview of the Auto Last Hop setting (11.x)

     

    http://support.f5.com/kb/en-us/solutions/public/13000/800/sol13876.html