What is the difference between SNAT and Self IP. Appears to me same. Could any please explain briefly.
m1978,
A Self IP is an IP address on the BIG-IP itself, is associated to a VLAN and an interface and can be a non-floating or floating one. Please see the following link: Manual Chapter: Self IP Addresses.
A SNAT is used in address translation of source IP address. See this link: Overview of SNAT features.
The link between the two is if you configure SNAT Automap on a virtual server it will translate the source address from being the original client IP address, to a self IP on the BIG-IP (in a HA environment the floating one is preferred). This is so return traffic goes via the BIG-IP and does not asymmetrically route directly to the client.
Hope this helps,
N