Wanted to use same public IP for different VS

OK, here is what I am suggesting: Create another virtual server on Big-IP (let's name it VIP-PXY). Nat public IP to this VS on the FW. This VS (VIP-PXY) will not be associated with any pools. Instead you will use a local traffic policy to forward inbound http traffic to VIP1, VIP2, VIP3 based on hostnames. You will need to create LT policy as follow:

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Create new Local traffic policy

Strategy: first-match
Requires: http
Controls: forwarding
Now you will need to create 3 rules (one for each host name)
Rule1:

IN conditions section specify below:

Operand:http-host

Event:  request

Selector:host

Condition:equals

Values:x.abc.com

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In Actions sections specify following:


Target: forward

Event:  request

Action: select

Parameters: virtual-server

Value: select VIP1 from dropdown (VIP1, VIP2 and VIP3 all need to be in the same partition)

Now create 2 more rules for VIP2 (y.abc.com) and VIP3 (z.abc.com) based on the policy rule for VIP1.

Associate policy with VS (VIP-PXY) under VS resources. You will need to associate http profile with VS (VIP-PXY) and set address translation to SNAT AutoMap.