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kridsana_52318's avatar
kridsana_52318
Icon for Nimbostratus rankNimbostratus
Jul 27, 2016

How F5 choose IP from SNAT pool

Hi

 

I've to create outbound VS with pool member of multiple link (example below)

 

F5 VIP: 0.0.0.0/0 with irule choose pool and snat pool

 

SNAT pool on F5: { 10.10.10.100, 20.20.20.200 }

 

Pool member of F5: { 10.10.10.1, 20.20.20.1 } is IP link

 

How F5 choose IP from SNAT pool? example: If F5 LB client to link IP 10.10.10.1 , Did F5 accurately choose IP 10.10.10.100 to NAT ?

 

And If we have only IP 20.20.20.200 in SNAT pool. Is it will break application? cause src IP outgoing is 20.20.20.200 but it LB to link 10.10.10.1

 

Thank you very much

 

application delivery
iRules
LTM

1 Reply

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  • boneyard's avatar
    boneyard
    Icon for MVP rankMVP
    Jul 27, 2016

    yeah it will most likely cause asymmetric routing or even not work at all when the source IP doesn't match the router network it goes through.

     

    isn't AutoMap an option? else you will have to do SNAT based on the poolmember selection. if poolmember 10.10.10.1 then SNAT 10.10.10.100.