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Forum Discussion

EIT_Network's avatar
EIT_Network
Icon for Altostratus rankAltostratus
Feb 07, 2019

SNAT-AutoMap , IP Enforcer & AXR

Hi All,   Would like to have clarity of "Source Address Translation" Option Under VS in LTM. While drop down there are 03 available options. 1- SNAT , 2-AutoMap , 3- None. What are specific imp...
application delivery
LTM
Dylan_375544's avatar
Dylan_375544
Icon for Cirrocumulus rankCirrocumulus
Feb 07, 2019

Well, for SNAT:

 

Automap basically means that the system will translate the source address from the clients original address to a floating IP on the BIG-IP. It will pick a floating IP over a non floating one even if the non floating one is in the correct subnet, so make sure you have a floating in the correct subnet to reach your backend servers.

 

SNAT without automap basically means that the system will SNAT to a POOL of IP addresses that you have configured.

 

NONE means that the system will not translate the clients source IP address. That can cause asynchronous routing if the BIG-IP is not the default gateway for your backend servers.

 

Hope that helps! If it does please up-vote and select this answer, it'd be greatly appreciated!

 

-Dylan

 

Dylan_375544's avatar
Dylan_375544
Icon for Cirrocumulus rankCirrocumulus
Feb 08, 2019

Yes, that is correct for Automap.

 

HERE is info on how you add the X-Forwarded-For header.

 

Not sure what you mean by "clear SNAT with example"

 

SNAT without Automap would require you to configure a list of IP addresses that the system would STAT to rather than it SNATing to a floating IP address.

 

If your BIG-IP is NOT your default gateway for your backend servers, you would need to have SNAT or SNAT Automap enabled for the traffic to be forced back through the BIG-IP on its way back to the client.