If pool nodes of a dCache instance are connected to a
secondary interface of the GridFTP door, e.g. because they
are in a private subnet, the GridFTP door will still tell
the pool to connect to its primary interface, which might be
unreachable.
The reason for this is that the control communication between
the door and the pool is done via the network of TCP
connections which have been established at start-up. In the
standard setup this communication is routed via the dCache
domain. However, for the data transfer, the pool connects to
the GridFTP door. The IP address it connects to is sent by
the GridFTP door to the pool via the control
connection. Since the GridFTP door cannot find out which of
its interfaces the pool should use, it normally sends the IP
address of the primary interface.
Tell the GridFTP door explicitly which IP it should send to
the pool for the data connection with the
gsiftpAdapterInternalInterface
property.
Example:
E.g. if the pools should connect to the secondary interface
of the GridFTP door host which has the IP address
10.0.1.1, set
gsiftpAdapterInternalInterface=10.0.1.1
in the /etc/dcache/dcache.conf file.