FreeTDS Development Group

[Peter Deacon <peterd AT iea-software.com>]

On Mon, 29 Oct 2012, Steven Peterson wrote:

> > However, this is a general problem: in general, to connect to remote
> > machines, all clients, not only FreeTDS, need to present themselves as
> > originating from an acceptable source.  The natural answer is to use
> > network address translation at the source.

> I'd love to help, but I'm afraid I do not have the C skills to provide a 
> patch.  My interim solution will be as you suggest -- use the iptables 
> nat table to change the source IP address based on the port, (I can 
> specify a dummy port in FreeTDS, and use that as a flag to iptables to 
> rewrite the 'from' IP).  While this may be the general solution, it is 
> probably getting further into linux than many FreeTDS users are able. 
> So, please consider a bindAddress parameter as a suggestion to make 
> using FreeTDS easier for people who are not so familiar with linux.

FWIW unless you bind to a specific interface the kernel normally selects 
source address based on local knowledge of routing table.

If you add a route preferencing destination OS will pick the right 
source address for you.

For example:

route add -host mysqlserver mysourceinterface
(route add -host 10.0.0.1 eth1:1)

regards,
Peter