transfer of data from one machine to another

[akhadar]

What is the entry
NAMES.DEFAULT_DOMAIN in sqlnet.ora file.If it is not commented out then
suppose it is like NAMES.DEFAULT_DOMAIN = world add this 'world ' to your tnsnames.ora file connection string like

orcl.word =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.0.77)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = orcl)
)
)

[DaPi]

Unless you're working in a complex, multi-domain set up (in which case, you don't need help from me!), I would suggest getting rid of the NAMES.DEFAULT_DOMAIN from sqlnet.ora

[adrianomp]

1) To easily understand db links, just imagine the local server as a "client", and the remote server as the "server". It's the same NET8. You may have the tnsnames configuration on your client or anywhere else, just copy it to the local server and test the db link again.

2) Your link has the name "md". If you have initialization parameter GLOBAL_NAMES set to TRUE, the db link name should be the same as the remote server. Maybe that's your problem, think about changing that parameter or recreating the db link as ORCL.WORLD.