iis using which ip for outbound connection?

I have a server with multiple websites, each with their own ip address. all ip address are binded to the nic.

lets say website A uses a script to make an outbound connection to outsideserver1.com.
what would be the ip address of the outbound connection?

would it be the websites ip address?
would it be the servers ip address?

and why?
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depends on the ip address of the destination.  you can look at your servers routing table to tell which ip address it will use.

open a command prompt and type

route print

the output will show a list of network destinations and then it will show the interface it will use to reach that destination.
If the outsideserver1.com is not on the local machine/network, it should use the default gateway and the IP in the same network as the default gateway.
the "from" ip in the packet I beleive would be the main ip for the server, not one if the additional IPs you have you have added in the "advanced" properties for the TCP/IP protocol bound for the adapter that is assuming there's only a single adapter in the machine.  If there's multiple adapters in the machine than nic binding order would come in to play, but I won't go into that unless you say so.  The default gateway might determine the destination but it doesn't necessarily influence the nic used to send the packet.  IIRC, if two adapters are on the same network, the packet will simply go out (have the mac address of) the first adapter in the binding order.

I don't really know the reason that MS chose the first IP on an adapter other than it makes the most sense.  Why pick the second one :)?

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