The local machine can be connected to the same LAN. When other machines are connected, the TNS connection times out-caused by Firewall

In the afternoon, I am going to test how to create a materialized view for dblink,

Therefore, create a dblink to connect to the local machine on another database. After the connection is established, it is found that the following statements are directly executed in PLSQL.

Select * from B @ fgisdb;

Tip:

ORA-12170: TNS: Connection timeout
I thought it was a database version problem (the local machine is 11 GB, and the other is 10 Gb). I created a dblink for the database connected to the local database for 10 Gb, and found that the database can be connected normally,

Next, I went to the 10 Gb database and used the command window to try to log on to the local database. I found the same error:

 

SQL> conn fyzh_ora/fyzh_ora @ fgisdb
Error:
ORA-12170: TNS: Connection timeout

 

I found it on the internet that it may be a firewall problem. As a result, I can shut down the Windows Firewall (360 was disabled at the beginning, but 360 was not affected ).

 

Note:

If you create a 10g to 11g dblink, note that the user password of the connected 11g database should be changed to uppercase, because the 11g is case sensitive, and the 10g is capitalized by default, therefore, when the password of a Database User of 11g is lower case, but 10g is connected to 11g through dblink, the password is converted to upper case, so the following error is prompted:

Error is located in row 1st:
ORA-01017: invalid username/password; logon denied
ORA-02063: followed by line (from dblinkname13)

Solution: change the password of a user under 11 GB to uppercase