[comp.protocols.tcp-ip] Obtaining internet addresses

booloo@lll-lcc.llnl.gov (Mark Boolootian) (02/02/89)

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	Is it possible (under Ultrix 2.0) for a server to obtain the internet
address that the client used to contact the server?  My need to know this is
based on the following situation:  I have written an ftp gateway server which
we would like to gateway to two machines.  User should be able to specify
either machine using the normal ftp client syntax:
	
		ftp mach1 
		    or
		ftp mach2

The host table on the client machine will contain distinct internet addresses
for mach1 and mach2; however, they will have to resolve to the same physical
address since there is only a single ethernet interface on the gateway machine.
So, if the ftp server had some way of determining the internet address that was
used to contact it, the server could gateway to the appropriate machine.
	My guess is that, even if this information did exist, there is no way
to get at it.  In either case, if anyone has any suggestions as to how I might
solve this problem, I will heap praise upon thou.
	Thanks for reading this.
mb

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booloo@lll-lcc.llnl.gov (Mark Boolootian) (02/03/89)

In article <2266@lll-lcc.llnl.gov> booloo@lll-lcc.llnl.gov.UUCP I write:
>
>The host table on the client machine will contain distinct internet addresses
>for mach1 and mach2; however, they will have to resolve to the same physical
>address since there is only a single ethernet interface on the gateway machine.

After looking through some source code, I have determined that it isn't 
actually possible to have two ip addresses resolve to a single physical
address (at least in the case of a vax running Ultrix).  So my question 
can't be answered (at least to my liking).
mb



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