Hello,

First post,  searched around for an answer but maybe I'm not using the
proper lingo.   sorry in advance if this has been covered previously.



3 machines involved,  3rd is where commands are being issued from (tor-hm1)
 it is local to tor-xfer.

tor-hm1 - local network - behind NAT
tor-xfer - local network - behind NAT
chn-xfer remote network - public IP

This command works as expected,  moving data from tor-xfer to chn-xfer,

[hpcdata1@tor-hm1 ~]$ globus-url-copy -vb -cd -p 2 sshftp://
hpcda...@tor-xfer.removed.com/var/tmp/outtest.gz sshftp://hpcdata1@chn-xfer.
removed.com/var/tmp/outtest.gz

Attempting to move data in the other direction from chn to tor,  this
command will fail:

[hpcdata1@chn-xfer ~] globus-url-copy -vb -cd -p 2 sshftp://
hpcda...@chn-xfer.removed.com/var/tmp/chn-300k.fl sshftp://
hpcda...@tor-xfer.removed.com/var/tmp/chn-300k.fl

tor-hm1,  and tor-xfer are RFC1918 numbered and behind a NAT firewall with
1 to 1 mapping to an outside address on the firewall.       Any traffic
hitting this outside IP will be forwarded to tor-xfer.  THis has been
tested and confirmed to work,  there are no readability issues from the
remote network for any ports.

chn-xfer has an interface on a rotatable public IP,  no NAT.

tor-hm1 and tor-xfer use internal DNS.    The answers returned are not the
same as what the internet name servers will return when asking for host
lookups. think split dns.

What appears to be happening is when tor-hm1 contacts chn-xfer,   it asks
it to  "connect to this IP and send this file",  the problem is it is
telling chn-xfer to connect back to the RFC1918 IP address,  not the public
one.  which of course it can't reach.  This was verified via packet trace,
 chn-xfer attempts to connect to tor-xfer's internal IP.



*My question:,  Is there a method to force the hostname to be passed over
to the remote server instead of the IP, so the remote end does the lookup?*
  If chn-xfer did its own lookup on the name,  it would get the 'proper' IP
to use and things would likely be good again.



 While I could be wrong,  it would seem to be a better idea to have the
local NS used instead of the requester doing this for them,  what is the
thinking here?  Just curious really.

thanks for your time,
greg

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