globus-url-copy ignores GLOBUS_HOSTNAME; request to document GLOBUS_FTP_CLIENT_DATA_IP

[RubenGarcia]

On a machine behind NAT, GLOBUS_HOSTNAME can normally be used to indicate the external IP to connect to. But globus-url-copy is sending the wrong IP to the server:

/usr/local/globus-6/bin/globus-url-copy -vb -fast ftp://sunn-dtn.es.net:2811/data1/10G.dat file:///tmp/test.out
Source: ftp://sunn-dtn.es.net:2811/data1/
Dest: file:///tmp/
10G.dat -> test.out

        0 bytes         0.00 MB/sec avg         0.00 MB/sec inst

error: globus_ftp_client: the server responded with an error
500 500-Command failed. : globus_gridftp_server_file.c:globus_l_gfs_file_server_write_cb:3163:
500-callback failed.
500-globus_xio_tcp_driver.c:globus_l_xio_tcp_system_connect_cb:2022:
500-Unable to connect to 192.168.128.90:35309
500-globus_xio_system_select.c:globus_l_xio_system_handle_write:1108:
500-System error in connect: Network is unreachable
500-globus_xio: A system call failed: Network is unreachable
500 End.

export GLOBUS_HOSTNAME=138.246.234.17
/usr/local/globus-6/bin/globus-url-copy -vb -fast ftp://sunn-dtn.es.net:2811/data1/10G.dat file:///tmp/test.out
Source: ftp://sunn-dtn.es.net:2811/data1/
Dest: file:///tmp/
10G.dat -> test.out

        0 bytes         0.00 MB/sec avg         0.00 MB/sec inst

error: globus_ftp_client: the server responded with an error
500 500-Command failed. : globus_gridftp_server_file.c:globus_l_gfs_file_server_write_cb:3163:
500-callback failed.
500-globus_xio_tcp_driver.c:globus_l_xio_tcp_system_connect_cb:2022:
500-Unable to connect to 192.168.128.90:53139
500-globus_xio_system_select.c:globus_l_xio_system_handle_write:1108:
500-System error in connect: Network is unreachable
500-globus_xio: A system call failed: Network is unreachable
500 End.

/usr/local/globus-6/bin/globus-hostname
138.246.234.17

[RubenGarcia]

Also, GLOBUS_DOMAIN_NAME, used in common/source/library/globus_libc.c, is undocumented.

[RubenGarcia]

The problem seems to be a different undocumented environment variable: GLOBUS_FTP_CLIENT_DATA_IP, used in gridftp/control/source/globus_ftp_control_data.c line 2924

[RubenGarcia]

When setting GLOBUS_FTP_CLIENT_DATA_IP, I confirm the transfer was successful.
Please document the relevant environment variables and close this issue.

[RubenGarcia]

Patch is available
#135

[fscheiner]

Fixed in GCT 6.2.20201212 maintenance release.